Watlow CLS200, MLS300, CAS200 User Manual

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CLS200, MLS300, and CAS200

Communications Speciﬁcation

Watlow Anafaze

Repairs and Returns:

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Part No. 0600-1015-5100. Revision 3.0 November 2003

Information in this manual is subject to change without notice. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form without written permission from Watlow Anafaze.

Warranty

Watlow Anafaze, Incorporated warrants that the products furnished under this Agreement will be free from defects in material and workmanship for a period of three years from the date of shipment. The customer shall provide notice of any defect to Watlow Anafaze, Incorporated within one week after the Customer's discovery of such defect. The sole obligation and liability of Watlow Anafaze, Incorporated under this warranty shall be to repair or replace, at its option and without cost to the Customer, the defective product or part.

Upon request by Watlow Anafaze, Incorporated, the product or part claimed to be defective shall immediately be returned at the Customer's expense to Watlow Anafaze, Incorporated. Replaced or repaired products or parts will be shipped to the Customer at the expense of Watlow Anafaze, Incorporated.

There shall be no warranty or liability for any products or parts that have been subject to misuse, accident, negligence, failure of electric power or modiﬁcation by the Customer without the written approval of Watlow Anafaze, Incorporated. Final determination of warranty eligibility shall be made by Watlow Anafaze, Incorporated. If a warranty claim is considered invalid for any reason, the Customer will be charged for services performed and expenses incurred by Watlow Anafaze, Incorporated in handling and shipping the returned unit.

If replacement parts are supplied or repairs made during the original warranty period, the warranty period for the replacement or repaired part shall terminate with the termination of the warranty period of the original product or part.

The foregoing warranty constitutes the sole liability of Watlow Anafaze, Incorporated and the customer's sole remedy with respect to the products. It is in lieu of all other warranties, liabilities, and remedies. Except as thus provided, Watlow Anafaze, Inc. disclaims all warranties, express or implied, including any warranty of merchantability or ﬁtness for a particular purpose.

Please Note:

External safety devices must be used with this equipment.

Contents

Overview........................................................................ 1

In This Manual ............................................................ 1

Chapter 1: ANAFAZE/AB Protocol............................. 3

Protocol Syntax

Control Codes.............................................................. 3

Transaction Sequence.................................................. 4

Packet Format.............................................................. 6

Codes in a Packet ........................................................ 6

Error Checking

Block Check Character (BCC).................................... 8

Cyclic Redundancy Check (CRC)............................... 9

.................................................................3

..................................................................8

Examples ...........................................................................10

Block Read .................................................................. 10

Block Write ................................................................. 13

Message Data ....................................................................14

Data for a Read Command.......................................... 14

Data for a Write Command ......................................... 15

Two-Byte Data Types ................................................. 15

Figuring Block Size..................................................... 15

Anafaze/AB Data Table Summary ....................................16

Ordering of Heat and Cool Channel Parameters......... 17

Ordering of Ramp-Soak Profile Parameters................ 17

Anafaze/AB Protocol Data Table................................ 17

Chapter 2: Modbus-RTU Protocol............................... 21

Overview ...........................................................................21

Transactions on Modbus-RTU Networks ................... 21

The Query-Response Cycle......................................... 22

Serial Transmission..................................................... 22

Message Framing ........................................................ 23

CRC Error Checking ................................................... 25

Function Codes............................................................ 26

Writing Data................................................................ 30

Reading Data............................................................... 30

Examples ...........................................................................31

Read Examples............................................................ 31

Write Examples........................................................... 32

Modbus-RTU Data Table Summary ..................................33

Ordering of Heat and Cool Channel Parameters......... 34

Ordering of Ramp-Soak Profile Parameters................ 34

Relative and Absolute Modbus Addresses.................. 35

Modbus-RTU Protocol Data Table ............................. 35

Communications Speciﬁcation i

Contents

Chapter 3: Controller Parameter Descriptions ........... 39

Correlating Menu Items with Parameters .........................39

Parameters (by number) ....................................................45

Proportional Band/Gain (0)......................................... 45

Derivative Term (1)..................................................... 45

Integral Term (2) ......................................................... 45

Input Type (3).............................................................. 46

Output Type (4)........................................................... 47

Setpoint (5).................................................................. 48

Process Variable (6) .................................................... 48

Output Filter (7) .......................................................... 48

Output Value (8).......................................................... 49

High Process Alarm Setpoint (9) ................................ 49

Low Process Alarm Setpoint (10) ............................... 49

Deviation Alarm Band Value (11) .............................. 49

Alarm Deadband (12).................................................. 49

Alarm_Status (13) ....................................................... 50

Ambient Sensor Readings (15) ................................... 52

Pulse Sample Time (16) .............................................. 52

High Process Variable (17) ......................................... 52

Low Process Variable (18).......................................... 52

Precision (19) .............................................................. 53

Cycle Time (20) .......................................................... 54

Zero Calibration (21)................................................... 54

Full Scale Calibration (22) .......................................... 54

Digital Inputs (25) ....................................................... 54

Digital Outputs (26) .................................................... 55

Override Digital Input (28) ......................................... 55

Override Polarity (29) ................................................. 55

System Status (30)....................................................... 56

System Command Register (31) ................................. 56

Data Changed Register (32) ........................................ 57

Input Units (33) ........................................................... 57

EPROM Version Code (34) ........................................ 58

Options Register (35) .................................................. 58

Process Power Digital Input (36) ................................ 59

High Reading (37)....................................................... 59

Low Reading (38)........................................................ 59

Heat/Cool Spread (39)................................................. 59

Startup Alarm Delay (40)............................................ 60

High Process Alarm Output Number (41)................... 60

Low Process Alarm Output Number (42) ................... 60

High Deviation Alarm Output Number (43)............... 60

Low Deviation Alarm Output Number (44)................ 60

Channel Profile and Status (46) .................................. 61

Current Segment (47).................................................. 62

Segment Time Remaining (48) ................................... 62

Current Cycle Number (49)......................................... 62

Tolerance Alarm Time (50)......................................... 62

Communications Speciﬁcation ii

Contents

Last Segment (51) ....................................................... 62

Number of Cycles (52)................................................ 63

Ready Setpoint (53)..................................................... 63

Ready Event States (54) .............................................. 63

Segment Setpoint (55)................................................. 64

Triggers and Trigger States (56) ................................. 64

Segment Events and Event States (57)........................ 65

Segment Time (58)...................................................... 66

Tolerance (59) ............................................................. 66

Ramp/Soak Flags (60)................................................. 66

Output Limit (61) ........................................................ 67

Output Limit Time (62)............................................... 67

Alarm_Control (63)..................................................... 68

Alarm_Acknowledge (64)........................................... 68

Alarm_Mask (65) ........................................................ 68

Alarm_Enable (66)...................................................... 68

Output Override Percentage (67) ................................ 69

AIM Fail Output (68) .................................................. 69

Output Linearity Curve (69)........................................ 70

SDAC Mode (70) ........................................................ 70

SDAC Low Value (71)................................................ 70

SDAC High Value (72)............................................... 70

Save Setup to Job (73)................................................. 71

Input Filter (74) ........................................................... 71

Loop Alarm Delay (75)............................................... 71

Loop Names (77)......................................................... 71

T/C Failure Detection Flags (78) ................................ 72

Channel Name (78) ..................................................... 72

Restore PID Digital input (79) .................................... 72

Manufacturing Test (80).............................................. 72

PV Retransmit Primary Loop Number (81) ................ 73

PV Retransmit Maximum Input (82) .......................... 73

PV Retransmit Maximum Output (83)........................ 73

PV Retransmit Minimum Input (84) ........................... 73

PV Retransmit Minimum Output (85) ........................ 74

Cascade Primary Loop Number (86)........................... 74

Cascade Base Setpoint (87)......................................... 74

Cascade Minimum Setpoint (88)................................. 74

Cascade Maximum Setpoint (89)................................ 74

Cascade Heat/Cool Span (90) ..................................... 75

Ratio Control Master Loop Number (91).................... 75

Ratio Control Minimum Setpoint (92)........................ 75

Ratio Control Maximum Setpoint (93) ....................... 75

Ratio Control Control Ratio (94) ................................ 75

Ratio Control Setpoint Differential (95) ..................... 75

Loop Status (96).......................................................... 76

Output Type/Disable (97)............................................ 76

Output Reverse/Direct (98) ......................................... 76

Controller Type (99).................................................... 77

Ramp/Soak Profile Number (100)............................... 77

Communications Speciﬁcation iii

Contents

Controller Address (101)............................................. 77

Baud Rate (102) .......................................................... 77

Ready Events (103) ..................................................... 78

Appendix A: Communications Driver ......................... 79

Compiling and Linking ............................................... 79

Compatibility............................................................... 79

Commands................................................................... 79

Glossary ........................................................................ 83

Communications Speciﬁcation iv

Overview

This reference guide is designed to help applications software programmers with the following tasks:

Interface to Watlow Anafaze MLS300, CLS200, MLS and CLS con-

•

trollers, and the CAS200 and CAS scanners via serial communications.

•

Modify the communications Anafaze protocol driver in the Watlow

Anafaze Communications Driver Kit. (If you have the communications driver kit, you don’t need to read this manual unless you want to modify the communications driver.)

In This Manual

The following sections are included in this guide:

Chapter 1: Anafaze/AB Protocol . Gives an overview and explanation

of the Anafaze/Allen Bradley communications protocol.

Chapter 2: Modbus-RTU Protocol. Gives an overview and

explanation of the Modbus-RTU communications protocol

Chapters 1 and 2: Data Table Summary . Provides standard controller

data table maps for the parameters (one for each protocol).

Chapter 3: Parameters Description . Describes each parameter.

Appendix A : Communications driver.

Glossary: Explanation of commonly used terms and acronyms.

NOTE

This reference guide is not a tutorial. It does not explain how to use the controller; it is not a programming reference; it also does not explain PID control, alarms, linear scaling, or other topics that are explained in detail in the controller manuals. If you need additional information about a topic covered in this reference guide, consult the documentation included with your controller.

Communications Speciﬁcation 1

Overview

2 Communications Speciﬁcation

Chapter 1: ANAFAZE/AB Protocol

This section explains the ANAFAZE/Allen Bradley protocol used in Watlow Anafaze MLS, CLS, and CAS devices. These controllers operate on serial communications links (EIA/TIA-232 or EIA-TIA-485) at either 2400 or 9600 baud. They use 8 data bits, one or 2 stop bits, and no parity.

Protocol Syntax

The controllers use a half-duplex (master-slave) protocol to interface to high-level software. The host software is considered the “master” and the controller is considered the “slave.” In other words, the software can request information from the controller or download information to the controller. The controller can only respond to communications transactions initiated by the host software. The controller cannot initiate communications.

The controller and host software communicate by sending and receiving information in a “packet” format. A packet consists of a sequence of bytes in a speciﬁc format; it can be as large as 256 bytes of data. (For more information about packets, see the Packet Format section later in this chapter.)

The numbers in the packet are sent in binary format. However, our examples show bytes in hexadecimal format.

Control Codes

Watlow Anafaze abbreviates control codes this way:

Code Meaning

DLE

STX

ETX

ENQ

Escape code

Signals the start of the other control code character sequences.

Start Text

Begins a transmission.

End Te xt

Ends a transmission.

Request Resend

Tells the controller to resend its last ACK or NAK. Host software sends this command, and the controller responds to it.

Decimal

Value

16 10

02 02

03 03

05 05

Hex

Value

Communications Speciﬁcation 3

Chapter 1: ANAFAZE/AB Protocol

Code Meaning

ACK

NAK

Acknowledged

Signals that a syntactically correct packet has been received.

Not Acknowledged

Signals that an incorrect, invalid packet has been received.

Transaction Sequence

Here are the four steps in a transaction between the host software and the controller. The following example shows the transaction as an exchange of packets. The example also assumes that there are no communication errors in the exchange.

(1) The host software sends a packet that contains a read command or

write command. (2) The controller sends a DLE ACK to the host software. (3) The host software receives a reply packet from the controller. (4) The host software sends a DLE ACK.

The following ﬂowchart shows a transaction with no error handling.

Decimal

Value

06 06

21 15

Hex

Value

Send command packet

Receive DLE ACK

Receive valid reply packet

Send DLE ACK

( continued on next page )

NOTE

Due to the difference between the processing speeds of the controller and PCs, it may be necessary to delay the computer's acknowledgement (ACK) in order for the controller to receive it. A delay of 200 ms should sufﬁce.

4 Communications Speciﬁcation

Send command packet

Chapter 1: ANAFAZE/AB Protocol

This ﬂowchart shows one way for the host software to handle error checking. (If you are writing simple software, you don't necessarily need to use error handling routines as complete as these.)

Wait for DLE ACK or DLE NAK

Timed out?

Got ACK or NAK?

ACK

Wait for reply packet

YES

NAK

Send DLE ENQ

Sent DLE

ENQ

3 times?

Send DLE NAK

YES

Sent packet

3 times?

YES

Done

Timed out?

Packet valid?

YES

Send DLE ACK

Sent DLE

NAK 3 times?

YESYES

Communications Speciﬁcation 5

Chapter 1: ANAFAZE/AB Protocol

Packet Format

Messages are transmitted in the form of packets. Command and reply packets specify the source and destination addresses, whether to read or write, the block of data to read or write, etc.

A packet contains a sequence of binary bytes formatted this way:

DLE STX DLE ETX BCC/CRC

DATA

DST

SRC CMD

STS

TNSL TNSH ADDL

ADDH

Sending Control Codes

To send a control code, send a DLE before the control code to distinguish it from data.

Codes in a Packet

Sending a DLE as Data

When you send a byte with an x10, (a DLE), the controller and software interpret it as a command. Therefore, to send a DLE as data, send another DLE immediately before it (DLE DLE).

This section describes the sequence of bytes in a packet, in the order the host software or controller sends them.

DLE STX

The DLE STX byte signals the beginning of a transmission. Every

•

packet of information starts with the control codes DLE STX.

DST

•

The DST byte is the address of the destination device (usually a con-

troller; the ﬁrst Watlow Anafaze controller is at x08).

NOTE

When host software communicates with an MLS, a CLS, or a CAS in ANAFAZE or AB protocol, it does not send the controller’s actual address. Since the protocol reserves device addresses 0 to 7, the host software sends the value (controller address + 7), instead of the actual device address.

6 Communications Speciﬁcation

SRC

The SRC byte is the device address of the packet’s source. The host

•

software is usually designated address x00.

Chapter 1: ANAFAZE/AB Protocol

CMD

The CMD byte indicates the command that the host software sends

•

to the controller. The software sends a read (x01) or write (x08).

When the controller replies, it returns the read or write command

with the 7th bit set—in other words, it sends an x41 or x48.

STS (The Status Byte)

The controller uses the status byte, or STS, to return general status

•

and error ﬂags to the host software. (The controller ignores the status

byte in the host software's command packet.) The next table shows

status byte values and deﬁnitions.

An “x” in the status bytes below indicates that the associated nibble

•

may contain additional information. In most cases, the status byte is

composed of two independent nibbles. Each nibble is independent

so that two codes can return at once. For example, status code F1

indicates that data has changed (Fx) and the controller is being

updated through the front panel (x1).

Status

in Hex

00 The controller has nothing to report, or AB protocol is selected. 01 Access denied for editing. The controller is being updated through the

front panel. 02 AIM Comm failure. A0 A controller reset occurred. Cx The controller received a command that was not a block read or block

write. (Command Error) Dx The block write command attempted to write beyond a particular parame-

ter block boundary, or the host software attempted to access a data table

block that does not exist. (Data Boundary Error) Ex The Alarm_Status variable has changed. The software should query the

alarm status block to determine the particular alarm ﬂag that changed. Fx The controller altered shared data, either internally (from the ﬁrmware) or

externally (from the keyboard). The host software should read the Data

Changed Register to determine which data has been altered and update

its own run-time memory.

Description

TNSL

Least signiﬁcant byte of the transaction number. This is the ﬁrst half

•

of a “message stamp.”

The controller sends back the TNSL and TNSH exactly as it received

•

them, so host software can use the TNSL and TNSH bytes to keep track of message packets.

TNSH

•

Most signiﬁcant byte of the transaction number. This is the second

half of the “message stamp.”

Communications Speciﬁcation 7

Chapter 1: ANAFAZE/AB Protocol

ADDL

•

The low byte of the beginning data table address of the block of data

to read or write.

ADDH

The high byte of the beginning data table address of the block of data

•

to read or write.

DATA

•

The new values to be set with a write command, or the requested data

in a response to a read command.

DLE ETX

Every packet of information must end with the codes DLE ETX.

•

These codes signal the end of a transmission.

Error Checking

Block Check Character (BCC)

BCC or CRC

•

Communications packets include a one- or two-byte error check at

the end of the packet. There are two error check methods: Block Check Character (BCC), which requires 1 byte, and Cyclic Redundancy Check (CRC), which requires 2 bytes.

Watlow Anafaze recommends that you use the default error check method, BCC. It is easier to implement than CRC, and it is acceptable for most applications.

Select one error check method and conﬁgure both software and controller for that method, or they will be unable to communicate.

The error check methods work this way:

BCC checks the accuracy of each message packet transmission. It provides a medium level of security. The BCC is the 2’s complement of the 8-bit sum (modulo-256 arithmetic sum) of the data bytes between the DLE STX and the DLE ETX. (1’s complement +1)

8 Communications Speciﬁcation

BCC does not detect transposed bytes in a packet.

•

BCC cannot detect inserted or deleted 0 values in a packet.

•

If you have sent an x10 as data (by sending DLE x10) only one of the

•

DLE data bytes is included in the BCC’s sum (the DLE = x10 also).

For instance, the block read example shown in the examples section, adds x08 00 01 00 00 80 02 10. Note that the x10 representing DLE has been left out of the calculation. The sum should come to x9B.

1001 1011 = x9B 0110 0100 = 1’s complement +1 = 2’s complement

0110 0101 = x65

Cyclic Redundancy Check (CRC)

CRC is a more secure error check method than BCC. It provides a very high level of data security. It can detect:

All single-bit and double-bit errors.

•

All errors of odd numbers of bits.

•

All burst errors of 16 bits or less.

•

99.997% of 17-bit error bursts.

•

99.998% of 18-bit and larger error bursts.

The CRC is calculated using the value of the data bytes and the ETX byte. At the start of each message packet, the transmitter must clear a 16-bit CRC register.

Chapter 1: ANAFAZE/AB Protocol

When a byte is transmitted, it is exclusive-ORed with the right 8 bits of the CRC register and the result is transferred to the right 8 bits of the CRC register. The CRC register is then shifted right 8 times by inserting 0’s on the left.

Each time a 1 is shifted out on the right, the CRC register is ExclusiveORed with the constant value xA001. After the ETX value is transmitted, the CRC value is sent, least signiﬁcant byte (LSB) ﬁrst.

Below is a structured English procedure from AB Manual:

data_byte = all application layer data, ETX CLEAR CRC_REGISTER

FOR each data_byte

GET data_byte XOR (data_byte, right eight bits of CRC_REGISTER) PLACE RESULT in right eight bits of CRC_REGISTER

DO 8 times

Shift bit right, shift in 0 at left IF bit shifted =1

XOR (CONSTANT, CRC_REGISTER) PLACE RESULT in CRC_REGISTER

END IF

END DO END FOR TRANSMIT CRC_REGISTER as 2-byte CRC ﬁeld

Communications Speciﬁcation 9

Chapter 1: ANAFAZE/AB Protocol

Examples

The host software sends two kinds of commands: block reads and block writes. This section shows examples of both commands.

NOTE

If you read data from a loop set to SKIP, the controller will send an empty packet for that loop.

This section does not show how to calculate the error check value included with every packet. For help calculating the error check value, see the section on BCC or CRC earlier in this chapter.

Block Read

This example shows the block read command the host software sends, the controller’s responses, and the software's acknowledgment.

Situation: Read process variables for loops 1 to 8.

8 process variables 2 bytes each = 16 bytes from data table address

•

x0280.

•

Character values are represented in hex.

•

The sender is device address 0.

•

The destination is device address 8 (controller address 1).

•

The software sends transaction number 00.

10 Communications Speciﬁcation

Chapter 1: ANAFAZE/AB Protocol

The next picture shows the read command.

x10 02 08 00 01 00 00 00 80 02 10 10 10 03 65

DLE

Data (number of bytes to upload)

DLE

Data table address (LSB first)

Transaction number

Placeholder for status byte

Command (block read)

SRC (Source Device Address)

BCC value

ETX

DST (Destination Device Address)

STX

DLE

The controller sends a DLE-ACK:

x10 06

ACK

DLE

Communications Speciﬁcation 11

Chapter 1: ANAFAZE/AB Protocol

Then the controller sends its reply:

x10 02 00 08 41 00 00 00 (DATA) 10 03 C3

BCC value

ETX

DLE

Data (see below)

Transaction number

Status (00 = nothing to report)

Command

Source Device Address (controller address + 7)

Destination Device Address

STX

DLE

DATA:

xE2 01 09 02 E4 01 09 02 F1 01 DF 01 28 3C E4 01

Data, transmitted LSB first. Assuming precision for loops is –1: Loop 1 PV = x01E2 = 482, displayed as 48

Loop 2 PV = x0209 = 521, displayed as 52, etc.

Then the host software sends a DLE-ACK:

x10 06

ACK

DLE

12 Communications Speciﬁcation

Block Write

Chapter 1: ANAFAZE/AB Protocol

This section describes the block write command.

This example shows the block write command the master sends, the controller's responses, and the master's acknowledgment:

Situation: Write setpoint of 100 to loop 6.

• 1 setpoint 2 bytes per setpoint = 2 bytes to address x01CA (x01C0 +

xA, a 10-byte offset).

• Character values are represented in hexadecimal.

• The sender is device address 0.

• The destination is device address 8 (controller address 1).

• The software sends transaction number 00.

Here's a picture of the write command:

x10 02 08 00 08 00 00 00 CA 01 E8 03 10 03 3A

DLE

Data:

100 converts to 1000 = x03E8

(assuming the precision for loop 6 is –1) Data table address LSB first; x01CA = setpoint for loop

Transaction number

Placeholder for status byte

Command (block write)

SRC (Source Device Address)

DST (Destination Device Address)

STX

DLE

The controller sends a DLE-ACK:

x10 06

BCC value

ETX

DLE

ACK

Communications Speciﬁcation 13

Chapter 1: ANAFAZE/AB Protocol

Here’s a picture of the controller’s reply:

x10 02 00 08 48 00 00 00 10 03 B0

BCC value

ETX

DLE

Transaction number LSB/MSB

Status (00 = Nothing to report)

Command (block write)

Source device address

Destination device address

STX

DLE

Message Data

Data for a Read Command

Then the host software sends a DLE-ACK:

x10 06

ACK

DLE

Some messages contain data. What the data is and how much depends on the command used and the purpose of the message.

For a block read command, the data block consists of one byte that indicates the number of bytes to read (up to 244 bytes of data). The controller sends back a packet with a data block that contains the requested bytes.

14 Communications Speciﬁcation

Data for a Write Command

For a block write command, the block contains the bytes to write (up to 242 bytes of data). The controller sends back a message packet without data.

Two-Byte Data Types

For two-byte data types, like process variable and setpoint, the controller or host software sends the data in two-byte pairs with the least signiﬁcant byte ﬁrst.

Figuring Block Size

In order to read parameter values, you must know how many bytes to request. Parameter values are stored contiguously such that the setpoints for all the loops are stored together and in loop number order. For example, to read the deviation alarm deadband value for loops one to ﬁve, you would read ﬁve bytes starting at x05A0. Some parameters, such as setpoint, require two bytes of memory to store. So, for example, if you want to read the setpoint for four loops, you must read eight bytes.

Chapter 1: ANAFAZE/AB Protocol

Figure total block size in bytes for most loop parameters this way (do not forget the pulse loop):

(Data Size) * (Number of Loops)

Some parameters have values for both heat and cool. Figure block size for such a parameter this way:

2 * (Data Size) * (Number of Loops)

One exception is the units for each loop. Figure the data size for the units this way:

3 * (Number of Loops)

Parameters that are not loop parameters (like system status, digital inputs, or digital outputs) have speciﬁc data sizes. These data sizes are listed in the data table in the next section.

Communications Speciﬁcation 15

Chapter 1: ANAFAZE/AB Protocol

Anafaze/AB Data Table Summary

Each address holds one byte of data. Each parameter value requires one or two addresses to store depending on the type of data. The table below indicates the number of bytes for each data type. The data type for each parameter is indicated in the tables on the following pages.

Unsigned char (UC) 1 byte Signed char (SC) 1 byte Unsigned int (UI) 2 bytes Signed int (SI) 2 bytes

Because each loop is individually conﬁgurable, the number of instances of many parameters depends on the number of loops in the controller. Therefore, the number of bytes for these parameters is listed in the tables on the following pages in terms of the number of loops in the controller.

Data Type and Symbol Data Size

The storage requirements for some parameters depend on the number of digital inputs or digital outputs in the controller (MAX_DIGIN_BYTES and MAX_DIGOUT_BYTES). The storage of ramp-soak proﬁle parameters depend on the number of proﬁles (MAX_RSP), the number of segments per proﬁle (MAX_SEG), the number of triggers per segment (MAX_TRIG) and the number of events per segment (MAX_EVENT).

The table below shows the values for each of these factors. Use them to calculate the number of bytes for each parameter.

MAX_CH: 4CLS/CLS204 (4 loops + 1 pulse loop) 8CLS/CLS208 (8 loops + 1 pulse loop) 16CLS/CLS216/CAS200 (16 loops + 1 pulse loop) 16MLS/MLS316 (16 loops + 1 pulse loop) 32MLS/MLS332 (32 loops + 1 pulse loop)

MAX_DIGIN_BYTES 1 MAX_DIGOUT_BYTES 8 MAX_RSP 17 MAX_SEG 20 MAX_TRIG 2 MAX_EVENT 4

5 9 17 17 33

16 Communications Speciﬁcation

Ordering of Heat and Cool Channel Parameters

For parameters that have both heat and cool settings the heat values are stored in the ﬁrst registers and the cool values are stored in the registers starting at the listed address plus MAX_CH.

NOTE

Data table parameters 46 to 60 and 100 are ramp-soak parameters. They are only used in controllers with the ramp-soak option. Parameters 81 to 95 are enhanced features and only available in controllers with the enhanced features option.

Ordering of Ramp-Soak Proﬁle Parameters

Ramp-soak proﬁle parameters are ordered ﬁrst by proﬁle, then by segment where applicable. So, for example, the ﬁrst eight bytes of the Ready Events parameter are the ready segment event states for the ﬁrst proﬁle (proﬁle A) and the next eight bytes are for proﬁle B and so on. In the case of the segment triggers, the ﬁrst byte contains the ﬁrst trigger setting for the ﬁrst segment of proﬁle A, the second byte contains the settings for the second trigger for the ﬁrst segment of proﬁle A, the third byte contains the settings for the ﬁrst trigger for the second segment of proﬁle A and so on.

Chapter 1: ANAFAZE/AB Protocol

Anafaze/AB Protocol Data Table

Number Description

0 Proportional Band/Gain 0020 UC MAX_CH * 2 1 Derivative Term 0060 UC MAX_CH * 2 2 Integral Term 00A0 UI MAX_CH * 4 3 Input T ype 0120 UC MAX_CH 4 Output Type 0180 UC MAX_CH * 2 5 Setpoint 01C0 SI MAX_CH * 2 6 Process Variable 0280 SI MAX_CH * 2 7 Output Filter 0340 UC MAX_CH * 2 8 Output Value 0380 UI MAX_CH * 4 9 High Process Alarm Setpoint 0400 SI MAX_CH * 2 10 Low Process Alarm Setpoint 04C0 SI MAX_CH * 2 11 Deviation Alarm Band Value 05A0 UC MAX_CH 12 Alarm Deadband 0600 UC MAX_CH 13 Alarm Status 0660 UI MAX_CH * 2 14 Not used 06A0 128

Address

in Hex

Type Number of Bytes

Communications Speciﬁcation 17

Chapter 1: ANAFAZE/AB Protocol

Number Description

15 Ambient Sensor Readings 0720 SI 2 16 Pulse Sample Time 0730 UC 1 17 High Process Variable 0790 SI MAX_CH * 2 18 Low Process Variable 0850 SI MAX_CH * 2 19 Precision 0910 SC MAX_CH 20 Cycle Time 09D0 UC MAX_CH * 2 21 Zero Calibration 0A10 UI 2 22 Full Scale Calibration 0A16 UI 2 23 Not used 0A1C 4 24 Not used 0A20 64 25 Digital Inputs 0A60 UC MAX_DIGIN_BYTES 26 Digital Outputs 0A70 UC MAX_DIGOUT_BYTES 27 Reserved 0A80 UC MAX_DIGOUT_BYTES 28 Override Digital Input 0AA0 UC 1 29 Override Polarity 0AC0 UC 1 30 System Status 0AC8 UC 4 31 System Command Register 0ACC UC 1 32 Data Changed Register 0ACE UC 1 33 Input Units 0AD0 UC MAX_CH * 3 34 EPROM V ersion Code 0BF0 UC 12 35 Options Register 0BFC UC 1 36 Process Power Digital Input 0C00 UC 1 37 High Reading 0C60 SI MAX_CH * 2 38 Low Reading 0D20 SI MAX_CH * 2 39 Heat/Cool Spread 0DE0 UC MAX_CH 40 Startup Alarm Delay 0E20 UC 1 41 High Process Alarm Output Number 0E30 UC MAX_CH 42 Low Process Alarm Output Number 0E90 UC MAX_CH 43 High Deviation Alarm Output

Number 44 Low Deviation Alarm Output Number 0F50 UC MAX_CH 45 Not used 0F60 MAX_CH 46 Channel Proﬁle and Status 1000 UC MAX_CH 47 Current Segment 1020 UC MAX_CH 48 Segment Time Remaining 1040 UI MAX_CH * 2 49 Current Cycle Number 1080 UI MAX_CH * 2 50 Tolerance Alarm Time 10C0 UI MAX_CH * 2 51 Last Segment 1100 UC MAX_CH 52 Number Cycles 1120 UC MAX_CH 53 Ready Setpoint 1140 SI MAX_RSP * 2

Address

in Hex

0EF0 UC MAX_CH

Type Number of Bytes

18 Communications Speciﬁcation

Chapter 1: ANAFAZE/AB Protocol

Number Description

54 Ready Event States 1180 UC MAX_RSP *

55 Segment Setpoint 1280 SI MAX_RSP * 2 *

56 Triggers and Trigger States 1780 UC MAX_RSP*

57 Segment Events and Event States 1C80 UC MAX_RSP * MAX_SEG

58 Segment Time 2680 UI MAX_RSP * 2 *

59 Tolerance 2B80 SI MAX_RSP * 2 *

60 Ramp/Soak Flags 3080 UC MAX_CH 61 Output Limit 3200 SI MAX_CH * 4 62 Output Limit Time 3280 SI MAX_CH * 4 63 Alarm_Control 3300 UI MAX_CH * 2 64 Alarm_Acknowledge 33C0 UI MAX_CH * 2 65 Alarm_Mask 3480 UI MAX_CH * 2 66 Alarm_Enable 3540 UI MAX_CH * 2 67 Output Override Percentage 3600 SI MAX_CH * 4 68 AIM Failure Output 3690 UC 1 69 Output Linearity Curve 3700 UC MAX_CH * 2 70 SDAC Mode 3740 UC MAX_CH * 2 71 SDAC Low Value 3780 SI MAX_CH * 4 72 SDAC High Value 3800 SI MAX_CH * 4 73 Save Setup to Job 3880 UC 1 74 Input Filter 3890 UC MAX_CH 75 Loop Alarm Delay 38D0 UI MAX_CH * 2 76 Not used 3990 16 77 Loop Names

(CLS/CLS200 and MLS/MLS300) 78 T/C Failure Detection Flags

(CLS/CLS200 and MLS/MLS300) 78 Channel Name

(CAS/CAS200) 79 Restore PID Digital Input 4130 UC MAX_CH 80 Manufacturing Test 4160 UI 1 81 PV Retransmit Primary Loop

Number 82 PV Retransmit Maximum Input 4250 UI MAX_CH * 4 83 PV Retransmit Maximum Output 42E0 UC MAX_CH * 2

Address

in Hex

39A0 UI MAX_CH * 2

3A30 UC MAX_CH

3994 UC MAX_CH * 8

4200 UC MAX_CH * 2

Type Number of Bytes

MAX_DIGOUT_BYTES

MAX_SEG

MAX_SEG* MAX_TRIG

* MAX_EVENT

MAX_SEG

Communications Speciﬁcation 19

Chapter 1: ANAFAZE/AB Protocol

Number Description

84 PV Retransmit Minimum Input 4330 UI MAX_CH * 4 85 PV Retransmit Minimum Output 43C0 UC MAX_CH * 2 86 Cascade Primary Loop Number 4410 UC MAX_CH 87 Cacade Base Setpoint 4440 SI MAX_CH * 2 88 Cacade Minimum Setpoint 4490 SI MAX_CH * 2 89 Cascade Maximum Setpoint 44E0 SI MAX_CH * 2 90 Cascade Heat/Cool Span 4530 UI MAX_CH * 4 91 Ratio Control Master Loop Number 45C0 UC MAX_CH 92 Ratio Control Minimum Setpoint 45F0 SI MAX_CH * 2 93 Ratio Control Maximum Setpoint 4640 SI MAX_CH * 2 94 Ratio Control Control Ratio 4690 UI MAX_CH * 2 95 Ratio Control Setpoint Differential 46E0 SI MAX_CH * 2 96 Loop Status 4730 UC MAX_CH 97 Output Type/Disable 4760 UC MAX_CH * 2 98 Output Reverse/Direct 47B0 UC MAX_CH * 2 99 Controller T ype 47F0 UC 1 100 Ramp/Soak Proﬁle Number 4800 UC MAX_CH 101 Controller Address 4830 UC 1 102 Baud Rate 4840 UC 1

Address

in Hex

Type Number of Bytes

20 Communications Speciﬁcation

Chapter 2: Modbus-RTU Protocol

Overview

Transactions on Modbus-RTU Networks

Standard Modbus-RTU ports use an EIA/TIA-232C- or EIA/TIA-485/ 422-compatible serial interface that deﬁnes connector pinouts, cabling, signal levels, transmission baud rates, and parity checking.

Controllers communicate using a master-slave technique, in which only one device (the master) can initiate transactions (called “queries”). The other devices (slaves) respond by supplying the requested data to the master, or by taking the action requested in the query. Typical master devices include host processors and programming panels.

The master can address individual slaves, or initiate a broadcast message to all slaves. Slaves return a message (called a “response”) to queries that are addressed to them individually. Responses are not returned to broadcast queries from the master.

The Modbus-RTU protocol establishes the format for the master’s query by placing into it the device (or broadcast) address, a function code deﬁning the requested action, any data to be sent, and an error-checking ﬁeld. The slave’s response message is also constructed using ModbusRTU protocol. It contains ﬁelds conﬁrming the action taken, any data to be returned, and an error-checking ﬁeld. If an error occurred in receipt of the message, or if the slave is unable to perform the requested action, the slave will construct an error message and send it as its response.

Communications Speciﬁcation 21

Chapter 2: Modbus-RTU Protocol

The Query-Response Cycle

Query Message from Master

Device Address

Function Code

8-Bit Data Bytes

Error Check

Device Address

Function Code

8-Bit Data Bytes

Error Check

Response Message from Slave

The Query

The function code in the query tells the addressed slave device what kind of action to perform. The data bytes contain any additional information that the slave will need to perform the function. For example, function code 03 will query the slave to read holding registers and respond with their contents. The data ﬁeld must contain the information telling the slave which register to start at and how many registers to read. The error check ﬁeld provides a method for the slave to validate the integrity of the message contents.

The Response

If the slave makes a normal response, the function code in the response is an echo of the function code in the query. The data bytes contain the data collected by the slave, such as register values or status. If an error occurs, the function code is modiﬁed to indicate that the response is an error response, and the data bytes contain a code that describes the error. The error check ﬁeld allows the master to conﬁrm that the message contents are valid.

Serial Transmission

22 Communications Speciﬁcation

Each 8-bit byte in a message contains two 4-bit hexadecimal characters. This high character density allows better data throughput than ASCII for the same baud rate. Each message must be transmitted in a continuous stream.

Coding System

• 8-bit binary, hexadecimal 0 to 9, A to F

• 2 hexadecimal characters contained in each 8-bit ﬁeld of the message

Bits per Byte

• 1 start bit

Message Framing

Chapter 2: Modbus-RTU Protocol

• 8 data bits, least signiﬁcant bit sent ﬁrst

• 2 stop bits

• No parity

Error Check Field

Cyclical Redundancy Check (CRC)

Messages start with a silent interval of at least 3.5 character times. This is most easily implemented as a multiple of character times at the baud rate that is being used on the network (shown as T1-T2-T3-T4 in the ﬁgure below). The ﬁrst ﬁeld then transmitted is the device address.

The allowable characters transmitted for all ﬁelds are hexadecimal 0 to 9, A to F. Networked devices monitor the network bus continuously, including during the silent intervals. When the ﬁrst ﬁeld (the address ﬁeld) is received, each device decodes it to ﬁnd out if it is the addressed device.

Following the last transmitted character, a similar interval of at least 3.5 character times marks the end of the message. A new message can begin after this interval.

Similarly, if a new message begins earlier than 3.5 character times following a previous message, the receiving device will consider it a continuation of the previous message. This will set an error, as the value in the ﬁnal CRC ﬁeld will not be valid for the combined messages. A typical message frame is shown below.

START ADDRESS FUNCTION DATA CRC CHECK END

T1-T2-T3-T4 8 Bits 8 Bits

* 8 Bits 16 Bits T1-T2-T3-T4

Handling the Address Field

The address ﬁeld of a message frame contains 8 bits. Valid slave device addresses are in the range of 0 to 247 decimal. The individual slave devices are assigned addresses in the range of 1 to 247 decimal. A master addresses a slave by placing the slave address in the address ﬁeld of the message. When the slave sends its response, it places its own address in this address ﬁeld of the response to let the master know which slave is responding.

Handling the Function Field

The function code ﬁeld of a message frame contains 8 bits. Valid codes are in the range of 1 to 255 decimal. Not all these codes are applicable to all controllers. Current codes are described in the Function Codes section.

Communications Speciﬁcation 23

Chapter 2: Modbus-RTU Protocol

When a message is sent from a master to a slave device, the function code ﬁeld tells the slave what kind of action to perform. Examples are to read the On/Off states of a group of discrete coils or inputs; to read the data contents of a group of registers; or to read the diagnostic status of a slave.

When the slave responds to the master, it uses the function code ﬁeld to indicate either a normal (error-free) response or that some kind of error occurred (called an exception response). For a normal response, the slave simply echoes the original function code. For an exception response, the slave returns a code that is equivalent to the original function code with its most signiﬁcant bit set to a logic 1.

For example, a message from the master to slave to read a group of holding registers would have the following function code:

0000 0011 x3

If the slave device takes the requested action without error, it returns the same code in its response. If an exception occurs, it returns:

1000 0011 x83

In addition to its modiﬁcation of the function code for an exception response, the slave places a unique code into the data ﬁeld of the response message. This tells the master what kind of error occurred, or the reason for the exception.

The master device’s application program has the responsibility of handling exception responses. Typical processes are to post subsequent retries of the message, to try diagnostic messages to the slave, and to notify operators.

Contents of the Data Field

The data ﬁeld is constructed using sets of two hexadecimal numbers, in the range of x00 to xFF.

The data ﬁeld of messages sent from a master to slave devices contains additional information that the slave must use to take the action deﬁned by the function code. This can include items like descrete and register addresses, the quantity of items to be handled, and the count of actual data bytes in the ﬁeld.

For example, if the master requests a slave to read a group of holding registers (function code 03), the data ﬁeld speciﬁes the starting register and how many registers are to be read.

24 Communications Speciﬁcation

If no error occurs, the data ﬁeld of a response from a slave to a master contained the data requested. If an error occurs, the ﬁeld contains an exception code that the master application can use to determine the next action to be taken.

Chapter 2: Modbus-RTU Protocol

The data ﬁeld can be nonexistent (of zero length) in certain kinds of messages, where the function code alone speciﬁes the action.

Contents of the Error Checking Field

The error checking ﬁeld contains a 16-bit value implemented as two 8bit bytes. The error check value is the result of a Cyclical Redundancy Check (CRC) calculation performed on the message contents.

The CRC ﬁeld is appended to the message as the last ﬁeld in the message. When this is done, the low-order byte of the ﬁeld is appended ﬁrst, followed by the high-order byte. The CRC high-order byte is the last byte to be sent in the message.

How Characters are Transmitted Serially

When messages are transmitted on standard Modbus-RTU serial networks, each character or byte is sent in this order (left to right):

Least Signiﬁcant Bit (LSB).............Most Signiﬁcant Bit (MSB)

The bit sequence is:

Start 1 2 3 4 5 6 7 8 Stop Stop

CRC Error Checking

All messages include an error-checking ﬁeld that is based on a Cyclical Redundancy Check (CRC) method. The CRC ﬁeld checks the contents of the entire message. It is applied regardless of any parity check method used for the individual characters of the message.

The CRC ﬁeld is two bytes, containing a 16-bit binary value. The CRC value is calculated by the transmitting device, which appends the CRC to the message. The receiving device recalculates a CRC during receipt of the message, and compares the calculated value to the actual value it received in the CRC ﬁeld. If the two values are not equal, an error results.

The CRC is started by ﬁrst preloading a 16-bit register to all 1’s. Then a process begins of applying successive 8-bit bytes of the message to the current contents of the register. Only the 8 bits of data in each character are used for generating the CRC. Start and stop bits do not apply to the CRC.

During generation of the CRC, each 8-bit character is exclusive ORed with the register contents. Then the result is shifted in the direction of the least signiﬁcant bit (LSB), with a zero ﬁlled into the most signiﬁcant bit (MSB) position. The LSB is extracted and examined. If the LSB was a 1, the register is then exclusive ORed with a preset, ﬁxed xA001. If the LSB was a 0, no exclusive OR takes place.

Communications Speciﬁcation 25

Chapter 2: Modbus-RTU Protocol

Function Codes

This process is repeated until eight shifts have been performed. After the last shift, the next 8-bit byte is exclusive ORed with the register’s current value, and the process repeats for eight more shifts as described above. The ﬁnal contents of the register, after all the bytes of the message have been applied, is the CRC value.

The listing below shows the function codes supported by the CLS controllers. Codes are listed in decimal.

Code

in Hex

01 Read Coil Status 02 Read Input Status 03 Read Holding Registers 04 Read Input Registers 05 Force Single Coil 06 Preset Single Register 08 Diagnostics 0F Force Multiple Coils 10 Preset Multiple Registers

Name

x01 Read Coil Status

• Reads the On/Off status of discrete outputs (registers 00001 to

09999, the coils) in the slave. Broadcast is not supported.

x02 Read Input Status

• Reads the On/Off status of discrete inputs (registers 10001 to 19999)

in the slave. Broadcast is not supported.

x03 Read Holding Registers

• Reads the binary contents of holding registers (registers 40001 to

49999) in the slave. Broadcast is not supported.

26 Communications Speciﬁcation

x04 Read Input Registers

• Reads the binary contents of input registers (registers 30001 to

39999) in the slave. Broadcast is not supported.

x05 Force Single Coil

• Forces a single coil (registers 00001 to 09999, the coils) to either On

or Off. When broadcast, the function forces the same coil reference in all attached slaves.

Chapter 2: Modbus-RTU Protocol

NOTE

The function will override the controller’s memory protect state and the coil’s disable state. The forced state will remain valid until the controller’s logic next solves the coil. The coil will remain forced if it is not programmed in the controller’s logic.

x06 Preset Single Register

• Presets a value into a single holding register (registers 40001 to

49999). When broadcast, the function presets the same register reference in all attached slaves.

NOTE

The function will override the controller’s memory protect state. The preset value will remain valid in the register until the controller’s logic next solves the register contents. The register’s value will remain if it is not programmed in the controller’s logic.

x08 Diagnostics

• This function provides a series of tests for checking the communica-

tion system between the master and slave, or for checking various internal error conditions within the slave. Broadcast is not supported.

• The function uses a 2-byte subfunction code ﬁeld in the query to

deﬁne the type of test to be performed. The slave echoes both the function code and subfunction code in a normal response.

• Most of the diagnostic queries use a 2-byte data ﬁeld to send diag-

nostic data or controller information to the slave. Some of the diagnostics cause data to be returned from the slave in a data ﬁeld of a normal response.

Diagnostic Subfunctions

x00 Return Query Data

• The data passed in the query data ﬁeld is to be returned

(looped back) in the response. The entire response message should be identical to the query.

Subfunction Data Field (Query) Data Field (Response)

x00 00 Any Echo Query Data

x01 Restart Communications Option

• The slave’s peripheral port is to be initialized and restarted,

and all of its communications event counters are to be cleared. If the port is currently in Listen Only Mode, no

Communications Speciﬁcation 27

Chapter 2: Modbus-RTU Protocol

response is returned. This function is the only one that brings the port out of Listen Only Mode. If the port is not currently in Listen Only Mode, a normal response is returned. This occurs before the restart is executed.

Subfunction Data Field (Query) Data Field (Response)

x00 01 x00 00 Echo Query Data x00 01 xFF 00 Echo Query Data

x02 Return Diagnostic Register

• The contents of the slave’s 16-bit diagnostic register are

returned in the response.

Subfunction Data Field (Query) Data Field (Response)

x00 02 x00 00 Diagnostic Register

Contents

x04 Force Listen Only Mode

• Forces the addressed slave to its Listen Only Mode for

Modbus-RTU communications. This isolates it from the other devices on the network, allowing them to continue communicating without interruption from the addressed slave. No response is returned.

• When the slave enters its Listen Only Mode, all active com-

munication controls are turned off. The ready watchdog timer is allowed to expire, locking the controls off. While in this mode, any Modbus-RTU messages addressed to the salve or broadcast are monitored, but no actions will be taken and no responses will be sent.

• The only function that will be processed after the mode is

entered will be the Restart Communications Option function (function code 8, subfunction 1).

Subfunction Data Field (Query) Data Field (Response)

x00 04 x00 00 No Response

Returned

28 Communications Speciﬁcation

x0A Clear Counters

• Clears all Communication Event counters. Counters are

also cleared upon power-up.

Subfunction Data Field (Query) Data Field (Response)

x00 0A x00 00 Echo Query Data

x0B Return Bus Message Count

• The response data ﬁeld returns the quantity of messages that

the slave has detected on the communications system since its last restart, clear counters operations, or power-up.

Subfunction Data Field (Query) Data Field (Response)

x00 0B x00 00 Total Message Count

x0C Return Bus Communication Error Count

• The response data ﬁeld returns the quantity of CRC errors

encountered by the slave since its last restart, clear counters

Chapter 2: Modbus-RTU Protocol

operation, or power-up.

Subfunction Data Field (Query) Data Field (Response)

x00 0C x00 00 CRC Error Count

x0D Return Bus Exception Error Count

• The response data ﬁeld returns the quantity of Modbus-RTU

exception responses returned by the slave since its last restart, clear counters operation, or power-up.

Subfunction Data Field (Query) Data Field (Response)

x00 0D x00 00 Exception Error

Count

x0E Return Slave Message Count

• The response data ﬁeld returns the quantity of messages

addressed to the slave, or broadcast, that the slave has processed since its last restart, clear counters operation, or power-up.

Subfunction Data Field (Query) Data Field (Response)

x00 0E x00 00 Slave Message Count

x0F Return Slave No Response Count

• The response data ﬁeld returns the quantity of messages

addressed to the slave for which it returned a no response (neither a normal response nor an exception response), since its last restart, clear counters operation, or power-up.

Subfunction Data Field (Query) Data Field (Response)

x00 0F x00 00 Slave No Response

Count

x0F Force Multiple Coils

• Forces each coil (registers 00001 to 09999, the coils) in a sequence

of coils to either ON or OFF. When broadcast, the function forces the same coil references in all attached slaves.

x10 Preset Multiple registers

• Presets values into the sequence of holding registers (registers 40001

to 49999). When broadcast, the function presets the same register references an all attached slaves.

NOTE

The function will override the controller’s memory protect state. The preset values will remain valid in the registers until the controller’s logic next solves the register contents. The register values will remain if they are not programmed in the controller’s logic.

Communications Speciﬁcation 29

Chapter 2: Modbus-RTU Protocol

Writing Data

Reading Data

Watlow Anafaze controller memory is divided into approximately 100 parameters with unique control functions, such as temperature, set point, etc. Each parameter can have several Modbus-RTU addresses associated with it. When a Modbus-RTU host writes data to a controller parameter, the data sent may “command” controller ﬁrmware to perform speciﬁc functions. While host writes to multiple registers are permitted within a parameter, controller function hierarchies necessitate that only one parameter may be written at a time. Any data written past a parameter boundary is simply rejected.

The same parameter-based model is used for reading data from the controller’s Modbus-RTU interface. Modbus-RTU allows multiple register block reads for all types of registers. While Watlow Anafaze Modbus-RTU allows this type of read function, unexpected results may occur when reading registers that span across the boundaries of more than one parameter. A query from a Modbus-RTU host starts speciﬁc ﬁrmware processes that allow data to be formatted properly for the Modbus-RTU host. The sequence proceeds as follows:

(1) A query for data comes in from a Modbus-RTU host. (2) The controller determines what parameter among the hundred or so

is being queried.

(3) The data format from internal memory is converted for a Modbus-

RTU interface.

(a) Data for registers 40001 to 49999 and registers 30001 to

39999 are always two bytes in length. If the internal controller memory is in bit or byte size, the data is padded appropriately.

(b) The byte order from internal memory is LSB to MSB (least

signiﬁcant byte to most signiﬁcant byte. For example, the LSB ﬁrst value for 550.0° would be x7C 15. The MSB ﬁrst value would be x15 7C.) while the Modbus-RTU is MSB to LSB. Bytes are swapped as needed.

(4) Parameter data is sent to the Modbus-RTU interface.

When data from adjacent parameters is read and the parameters share the same data type (bit, byte or integer), the information is formatted correctly. However, if they do not share the same data type, host software could be written to pad and/or swap bytes as necessary.

30 Communications Speciﬁcation

Examples

Chapter 2: Modbus-RTU Protocol

Read Examples

The data read must be sequentially located. If you’re reading a coil rather than a register, you must offset the address by the location of the bit you wish to read.

Sample Packet for Host Transmission

Slave

Example

1. Reading

Address

in Hex

01 03 01 6C 00 01 45 EB PV of loop 2 (1600), controller 1 (single-point read)

2. Reading

03 03 01 D1 00 02 94 2C loops 4 and 5 heat outputs, of controller 3 (multipoint read)

3. Reading

01 02 03 82 00 10 D9 AA digital input 4, controller 1 (input status read)

Example

1. Reading PV of loop 2 (1600),

controller 1 (single-point read)

2. Reading loops 4 and 5 (50%, 60%) outputs (heat), of controller 3 (multipoint read)

3. Reading digital input 4, controller 1 (input status read)

Function

in Hex

Start

Address

High

in Hex

Start

Address

Low

in Hex

Number

of Points

High

in Hex

Number

of Points

Low

in Hex

CRC High

in Hex

Sample Packet for Slave Transmission

Slave

Address

in Hex

Function

in Hex

01 03 02 3E 80 84 1B

03 03 04 3F DE 4C 4A 2D 41

01 02 02 08 00 BE 78

Byte Count in Hex

Data

in Hex

CRC High

in Hex

CRC

Low

in Hex

CRC

Low

in Hex

Communications Speciﬁcation 31

Chapter 2: Modbus-RTU Protocol

Write Examples

The data written is echoed back to the controller.

Sample Packet for Host Transmission, a Single-Point Write

Example

4. Writing loop 1

gain (20), controller 4 (single-point write)

5. Writing digital output 30 (on), controller 2 (single coil write)

Example

4. Writing loop 1

gain (20), controller 4 (single-point write)

5. Writing digital output 30 (on), controller 2 (single coil write)

Slave

Address

in Hex

Function

in Hex

Address

High

in Hex

Address

Low

in Hex

Data High

in Hex

Data

Low

in Hex

CRC High

in Hex

04 06 00 00 00 14 89 90

02 05 03 A8 FF 00 0D AD

Sample Pac ket for Slave T ransmission, a Single-Point Write

Slave

Address

in Hex

Function

in Hex

04 06 00 00 00 14 89 90

02 05 03 A8 FF 00 OD AD

Address

High

in Hex

Address

Low

in Hex

Data High

in Hex

Data

Low

in Hex

CRC High

in Hex

CRC

Low

CRC

Low

32 Communications Speciﬁcation

Chapter 2: Modbus-RTU Protocol

Sample Packet for Host Transmission, a Multipoint Write

The data must be written to sequential locations.

Helpful hint: The string is longer for multiple write; checking the BYTE COUNT can help in determining if a command timeout is valid.

Example 6: Writing TI loops 3 (100) and 4 (150), controller

10.

Slave

Address

in Hex

Function

in Hex

Address

High

in Hex

Address

Low

in Hex

Number

Registers

High

in Hex

Number

Registers

Low

in Hex

Byte

Count

in Hex

Data

in Hex

CRC High

Hex

in Hex

0A 10 00 86 00 02 04 00 64 00 96 9F 70

Sample Packet for Slave Transmission, a multipoint write.

Number

Slave

Address

in Hex

Function

in Hex

Address

High

in Hex

Address

Low

in Hex

Registers

High

in Hex

0A 10 00 86 00 02 A1 5A

Number of

Registers

Low

in Hex

CRC

High

in Hex

Modbus-RTU Data Table Summary

Each addressable register holds two bytes of data. Each parameter value requires only one register to store any of these types of data. The data type for each parameter is indicated in the tables on the following pages.

CRC

Low

CRC

Low

Hex

Data Type and Symbol Data Size

Unsigned char (UC) 1 byte Signed char (SC) 1 byte Unsigned int (UI) 2 bytes Signed int (SI) 2 bytes

Because each loop is individually conﬁgurable, the number of instances of many parameters depends on the number of loops in the controller. Therefore, the number of registers for these parameters is listed in the tables on the following pages in terms of the number of loops in the controller.

Communications Speciﬁcation 33

Chapter 2: Modbus-RTU Protocol

The storage requirements for some parameters depend on the number of digital inputs or digital outputs to the controller (MAX_DIGIN and MAX_DIGOUT). The storage of ramp-soak proﬁle parameters depend on the number of proﬁles (MAX_RSP), the number of segments per proﬁle (MAX_SEG), the number of triggers per segment (MAX_TRIG), and the number of events per segment (MAX_EVENT).

The table below shows the values for each of these factors. Use them to calculate the number of registers for each parameter.

MAX_DIGIN 8 MAX_DIGOUT 35 MAX_RSP 17 MAX_SEG 20 MAX_TRIG 2 MAX_EVENT 4

5 9 17 17 33

NOTE

Data table parameters 46 to 60, 100 and 103 are ramp-soak parameters. They are only used in controllers with the ramp-soak option. Parameters 81 to 95 are enhanced features and are only available in controllers with the enhanced features option.

Ordering of Heat and Cool Channel Parameters

For parameters that have both heat and cool settings, the heat values are stored in the ﬁrst registers and the cool values are stored in the registers starting at the listed address plus MAX_CH.

Ordering of Ramp-Soak Proﬁle Parameters

Ramp-soak proﬁle parameters are ordered ﬁrst by proﬁle, then by segment where applicable. So, for example, the ﬁrst 35 registers of the Ready Events parameter are the ready segment event states for the ﬁrst proﬁle (proﬁle A), the next 35 registers are for proﬁle B, and so on. In the case of the segment triggers, the ﬁrst register contains the ﬁrst trigger setting for the ﬁrst segment of proﬁle A, the second register contains the settings for the second trigger for the ﬁrst segment of proﬁle A, the third register contains the settings for the ﬁrst trigger for the second segment of proﬁle A, and so on.

34 Communications Speciﬁcation

Relative and Absolute Modbus Addresses

In the tables on the following pages, absolute addresses are in decimal and relative addresses are in hexidecimal. Absolute addresses include the type of register. Refer to the absolute address to determine which function to use to read or write values (see the Function Codes on page

26).

Relative addresses indicate the register offset from the ﬁrst register of the particular type. For example, the ﬁrst register for the Derivative parameter is at 40067, which is offset 66 (x42) registers from the beginning of the holding registers at 40001.

Modbus-RTU Protocol Data Table

Chapter 2: Modbus-RTU Protocol

Number Description

0 Proportional Band/Gain 40001 0000 UC MAX_CH * 2 1 Derivative Term 40067 0042 UC MAX_CH * 2 2 Integral Term 40133 0084 UI MAX_CH * 2 3 Input T ype 40199 00C6 UC MAX_CH 4 Output Type 40265 0108 UC MAX_CH * 2 5 Setpoint 40331 014A SI MAX_CH 6 Process Variab le 40364 016B SI MAX_CH 7 Output Filter 40397 018C UC MAX_CH * 2 8 Output Value 40463 01CE UI MAX_CH * 2 9 High Process Alarm Setpoint 40529 0210 SI MAX_CH 10 Low Process Alarm Setpoint 40562 0231 SI MAX_CH 11 Deviation Alarm Band Value 40595 0252 UC MAX_CH 12 Alarm Deadband 40628 0273 UC MAX_CH 13 Alarm_Status 40661 0294 UI MAX_CH 14 Not used 40694 02B5 33 15 Ambient Sensor Readings 40727 02D6 SI 2 16 Pulse Sample Time 40729 02D8 UC 1 17 High Process Variable 40730 02D9 SI MAX_CH 18 Low Process Variable 40763 02FA SI MAX_CH 19 Precision 40796 031B SC MAX_CH 20 Cycle Time 40829 033C UC MAX_CH 21 Zero Calibration 40895 037E UI 2 22 Full Scale Calibration 40896 037F UI 2 23 Not used 40897 0380 1 24 Not used 40898 0381 1 25 Digital Inputs 10899 0382 Bit MAX_DIGIN 26 Digital Outputs 00907 038A Bit MAX_DIGOUT

Absolute

Address

Relative

Address in

Hex

Type

Number of

Registers

Communications Speciﬁcation 35

Chapter 2: Modbus-RTU Protocol

Number Description

27 Not used 40942 03AD UC 1 28 Override Digital Input 40943 03AE UC 1 29 Override Polarity 40944 03AF UC 1 30 System Status 40945 03B0 UC 4 31 System Command Register 40949 03B4 UC 1 32 Data Changed Register 40950 03B5 UC 1 33 Input Units 40951 03B6 UC MAX_CH * 3 34 EPROM V ersion Code 41050 0419 UC 1 35 Options Register 41062 0425 UC 1 36 Process Power Digital Input 41063 0426 UC 1 37 High Reading 41064 0427 SI MAX_CH 38 Low Reading 41097 0448 SI MAX_CH 39 Heat/Cool Spread 41130 0469 UC MAX_CH 40 Startup Alarm Delay 41163 048A UC 1 41 High Process Alarm Output

Number

42 Low Process Alarm Output

Number

43 High Deviation Alarm Output

Number

44 Low Deviation Alarm Output

Number 45 Not used 41296 050F 1 46 Channel Proﬁle and Status 41297 0510 UC MAX_CH 47 Current Segment 41330 0531 UC MAX_CH 48 Segment Time Remaining 41363 0552 UI MAX_CH 49 Current Cycle Number 41924 0783 UI MAX_CH 50 Tolerance Alarm Time 41957 07A4 UI MAX_CH 51 Last Segment 41990 07C5 UC MAX_CH 52 Number of Cycles 42023 07E6 UC MAX_CH 53 Ready Setpoint 42056 0807 SI MAX_RSP 54 Ready Event States 42089 0828 UC MAX_RSP *

55 Segment Setpoint 42174 087D SI MAX_RSP * MAX_SEG 56 Triggers and Trigger States 42834 0B11 UC MAX_RSP * MAX_SEG

57 Segment Events and Event

States 58 Segment Time 46794 1A89 UI MAX_RSP * MAX_SEG 59 Tolerance 47454 1D1D SI MAX_RSP * MAX_SEG 60 Ramp/Soak Flags 48114 1FB1 UC MAX_CH

Absolute

Address

41164 048B UC MAX_CH

41197 04AC UC MAX_CH

41230 04CD UC MAX_CH

41263 04EE UC MAX_CH

44154 1039 UC MAX_RSP * MAX_SEG

Relative

Address in

Hex

Type

Number of

Registers

MAX_DIGOUT

* MAX_TRIG

* MAX_EVENT

36 Communications Speciﬁcation

Chapter 2: Modbus-RTU Protocol

Number Description

61 Output Limit 48147 1FD2 SI MAX_CH * 2 62 Output Limit Time 48213 2014 SI MAX_CH * 2 63 Alarm_Control 48279 2056 UI MAX_CH 64 Alarm_Acknowledge 48312 2077 UI MAX_CH 65 Alarm_Mask 48345 2098 UI MAX_CH 66 Alarm_Enable 48378 20B9 UI MAX_CH 67 Output Override Percentage 48411 20DA SI MAX_CH * 2 68 AIM Fail Output 48477 211C UC 1 69 Output Linearity Curve 48478 211D UC MAX_CH 70 SDAC Mode 48544 215F UC MAX_CH * 2 71 SDAC Low Value 48610 21A1 SI MAX_CH * 2 72 SDAC High Value 48676 21E3 SI MAX_CH * 2 73 Save Setup to Job 48742 2225 UC 1 74 Input Filter 48743 2226 UC MAX_CH 75 Loop Alarm Delay 48776 2247 UI MAX_CH 76 Not used 48809 2268 1 77 Loop Names

(CLS/CLS200 and MLS/

MLS300) 78 T/C Failure Detection Flags

(CLS/CLS200 and MLS/

MLS300) 78 Channel Name

(CAS/CAS200) 79 Restore PID Digital Input 48909 22CC UC MAX_CH 80 Manufacturing Test

(CLS/CLS200 and MLS/

MLS300) 80 Manufacturing Test

(CAS/CAS200) 81 PV Retransmit Primary Loop

Number 82 PV Retransmit Maximum

Input 83 PV Retransmit Maximum

Output 84 PV Retransmit Minimum

Input 85 PV Retransmit Minimum

Output 86 Cascade Primary Loop

Number

Absolute

Address

48810 2269 UI MAX_CH * 2

48876 22AB UC MAX_CH

48876 22AB UC MAX_CH * 8

48942 22ED UI 1

49014 2235 UI 1

48943 22EE UC MAX_CH * 2

49009 2330 UI MAX_CH * 2

49075 2372 UC MAX_CH * 2

49141 23B4 UI MAX_CH * 2

49207 23F6 UC MAX_CH * 2

49273 2438 UC MAX_CH

Relative

Address in

Hex

Type

Number of

Registers

Communications Speciﬁcation 37

Chapter 2: Modbus-RTU Protocol

Number Description

87 Cacade Base Setpoint 49306 2459 SI MAX_CH 88 Cascade Minimum Setpoint 49339 247A SI MAX_CH 89 Cascade Maximum Setpoint 49372 249B SI MAX_CH 90 Cascade Heat/Cool Span 49405 24BC UI MAX_CH * 2 91 Ratio Control Master Loop

Number 92 Ratio Control Minimum

Setpoint 93 Ratio Control Maximum

Setpoint 94 Ratio Control Control Ratio 49570 2561 UI MAX_CH 95 Ratio Control Setpoint

Differential 96 Loop Status 49636 25A3 UC MAX_CH 97 Output Type/Disable 49669 25C4 UC MAX_CH * 2 98 Output Reverse/Direct 49735 2506 UC MAX_CH * 2 99 Controller T ype 49801 2647 UC 1 100 Ramp/Soak Proﬁle Number 49802 2649 UC MAX_CH 101 Controller Address 49835 C2AB UC 1 102 Baud Rate 49836 C2AC UC 1 103 Ready Events (Modbus-RTU) 49837 266C UC MAX_RSP *

Absolute

Address

49471 24FE UC MAX_CH

49504 251F SI MAX_CH

49537 2540 SI MAX_CH

49603 2582 SI MAX_CH

Relative

Address in

Hex

Type

Number of

Registers

MAX_DIGOUT

38 Communications Speciﬁcation

Chapter 3: Controller Parameter Descriptions

This section provides speciﬁc details for each data table parameter including data type, variable range, and default values where applicable.

The Controller Menus section on the next page shows all of the controller menus for MLS and CLS controllers. (Controller features and menus vary; not all of the menus shown here apply to each controller.) This is for reference only, to help you ﬁnd applicable controller parameters to test your software.

WARNING

The controller’s parameters are all read/write, and the controller does not check the content of data written to it. It is possible to write to any parameter, even though it may not be meaningful to do so.

Some of the controller’s functions are not listed as data table parameters in this chapter. If a parameter is not listed in this chapter, one of the following situations applies:

• The parameter is set only in the controller’s menus; it is not set in

host software. For example, jobs are loaded through the controller’s front panel only.

• The function may be a bit set in a byte in host software. For example,

the panel lock feature does not have its own parameter; it is set in the System Command register.

Correlating Menu Items with Parameters

There is not a one-to-one correspondence between parameters found on the controller menus and the data table items. Some parameters that appear separately on the controller’s display are combined when stored in the data table and when read or written via serial communications. The following tables lay out the correspondence between menu items and the data table.

Communications Speciﬁcation 39

Chapter 3: Controller Parameter Descriptions

In the following tables, “RS” in the Product(s) column indicates that the parameter is found in controllers equipped within the Ramp and Soak option ﬁrmware. Similarly, “EF” indicates that the parameter is found in controllers equipped with the Enhanced Features option.

Menu/Parameter Product(s) Parameter(s)

Single-Loop Display

Setpoint All Units 5 Process Variab le All Units 6 Heat Output Percent Not CAS/CAS200 8 Cool Output Percent Not CAS/CAS200 8 Control Mode Not CAS/CAS200 4 or 96 Process/Deviation/Sensor Alarms All Units 13, 64 System Alarms All Units 13, 15 Assign R/S Proﬁle RS 46 Ramp Soak Proﬁle RS 100 Current Segment RS 47 Time Remaining RS 48 Cycle Number RS 49 Set Mode RS 46 Reset RS 46

Global Menu

Load Setup From Job All Units Front Panel Only Job Save Number All Units 73 Job Select Dig Inputs All Units 23 Job Sel Dig Ins Active All Units 24 Output Override Dig Input Not CAS/CAS200 Front Panel Only Override Dig In Active Not CAS/CAS200 Front Panel Only Startup Alarm Delay All Units 40 Ramp/Soak Time Base RS 31 Keyboard Lock Status All Units 31 Power Up Output Status Not CAS/CAS200 31 Process Power Digin Not CAS/CAS200 Front Panel Only Controller Address Not CAS/CAS200 101 Communications Protocol All Units Front Panel Only Communications Err Check All Units Front Panel Only AC Line Freq All Units 31 Dig Out Polarity on Alarm All Units 31 Firmware Info All Units 34, 35, 99

Input Menu

Input T ype All Units 3 Loop Name Not CAS/CAS200 77 Channel Name CAS/CAS200 only 78

40 Communications Speciﬁcation

Chapter 3: Controller Parameter Descriptions

Menu/Parameter Product(s) Parameter(s)

Input Units All Units 33 Input Reading Offset All Units 17, 18 Reversed T/C Detect Not CAS/CAS200 78 Input Pulse Sample Time All Units 16 Display Format All Units 19 Input Scaling Hi PV All Units 17 Input Scaling Hi Rdg All Units 37 Input Scaling Lo PV All Units 18 Input Scaling Lo Rdg All Units 38 Input Filter All Units 74

Control Params Menu

Heat Control PB Not CAS/CAS200 0 Heat Control TI Not CAS/CAS200 2 Heat Control TD Not CAS/CAS200 1 Heat Control Filter Not CAS/CAS200 7 Cool Control PB Not CAS/CAS200 0 Cool Control TI Not CAS/CAS200 2 Cool Control TD Not CAS/CAS200 1 Cool Control Filter Not CAS/CAS200 7 Spread Not CAS/CAS200 39 Restore PID Digital Input Not CAS/CAS200 79

Outputs Menu

Heat Control Output Not CAS/CAS200 4 Heat Output Type Not CAS/CAS200 4, 97 Heat Output Cycle Time (TP) Not CAS/CAS200 20 SDAC Mode Not CAS/CAS200 70 SDAC Lo Value Not CAS/CAS200 71 SDAC Hi Value Not CAS/CAS200 72 Heat Output Action Not CAS/CAS200 4, 98 Heat Output Limit Not CAS/CAS200 61 Heat Output Limit Time Not CAS/CAS200 62 Sensor Fail Ht Output Not CAS/CAS200 67 Heat T/C Brk Out Avg Not CAS/CAS200 78 Heat Output Not CAS/CAS200 69 Cool Control Output Not CAS/CAS200 4 Cool Output Type Not CAS/CAS200 4, 97 Cool Output Cycle Time (TP) Not CAS/CAS200 20 SDAC Mode Not CAS/CAS200 70 SDAC Lo Value Not CAS/CAS200 71 SDAC Hi Value Not CAS/CAS200 72

Communications Speciﬁcation 41

Chapter 3: Controller Parameter Descriptions

Menu/Parameter Product(s) Parameter(s)

Cool Output Action Not CAS/CAS200 4, 98 Cool Output Limit Not CAS/CAS200 61 Cool Output Limit Time Not CAS/CAS200 62 Sensor Fail Cl Output Not CAS/CAS200 67 Cool T/C Brk Out Avg Not CAS/CAS200 78 Cool Output Not CAS/CAS200 69

Alarms Menu

Hi Proc Alarm Setpt All Units 9 Hi Proc Alarm Type All Units 63, 65 Hi Proc Alarm Output All Units 41 Dev Alarm Value All Units 11 Hi Dev Alarm Type All Units 63, 65 Hi Dev Alarm Output All Units 43 Lo Dev Alarm Type All Units 63, 65 Lo Dev Alarm Output All Units 44 Lo Proc Alarm Setpt All Units 10 Lo Proc Alarm Type All Units 63, 65 Lo Proc Alarm Output All Units 42 Alarm Deadband All Units 12 Alarm Delay All Units 40, 75

Manual I/O Test Menu

Digital Inputs All Units 25 Test Digital Output All Units 26 Digital Output Number All Units 26 Keypad Test All Units Front Panel only

42 Communications Speciﬁcation

Chapter 3: Controller Parameter Descriptions

Additional menus are found in controllers with Ramp and Soak and Enhanced Features options.

Menu/Parameter Product(s) Parameter(s)

Setup Loop PV Retransmit EF and RS

Heat Output Retrans PV EF and RS 81 PV Retransmit Minimum Input EF and RS 84 PV Retransmit Minimum Output EF and RS 85 PV Retransmit Maximum Input EF and RS 82 PV Retransmit Maximum Output EF and RS 83 Cool Output Retrans PV EF and RS 81 PV Retransmit Minimum Input EF and RS 84 PV Retransmit Minimum Output EF and RS 85 PV Retransmit Maximum Input EF and RS 82 PV Retransmit Maximum Output EF and RS 83 Setup Loop Cascade EF Cascade Primary Loop Number EF 86 Cascade Base Setpoint EF 87 Cascade Minimum Setpoint EF 88 Cascade Maximum Setpoint EF 89 Cascade Heat Span EF 90 Cascade Cool Span EF 90 Setup Loop Ratio Control EF Ratio Control Master Loop Number EF 91 Ratio Control Minimum Setpoint EF 92 Ratio Control Maximum Setpoint EF 93 Ratio Control Ctrl Ratio EF 94 Ratio Control SP Diff EF 95 Setup Ramp/Soak Proﬁle RS Edit Ramp & Soak Proﬁle RS Front Panel only Copy Setup From Proﬁle RS Front Panel only Out-of-Tolrnce Alarm Time RS 50 Ready Segment Setpoint RS 53 Ready Segment Edit Events RS Front Panel only Ready Event Output RS 54 External Reset Input Number RS Front Panel only Edit Segment Number RS Front Panel only Segment ## Seg Time RS 58 Segment ## Seg Setpt RS 55 Segment ## Edit Seg Events RS Front Panel only Seg ## Event # Output RS 57 Seg ## Ev# DO## Active State RS 57

Communications Speciﬁcation 43

Chapter 3: Controller Parameter Descriptions

Menu/Parameter Product(s) Parameter(s)

Segment ## Edit Seg Trggrs RS Front Panel only Seg ## Trig # Input NR RS 56 Seg ## Tr# DI## aCTIVE STATE RS 56 SEG ## TR# DI## TRIG RS 56 SEGMENT ## SEG TOLERANCE RS 59 SEGMENT ## LAST SEGMENT RS 51 REPEAT CYCLES RS 52

44 Communications Speciﬁcation

Parameters (by number)

Proportional Band/Gain (0)

Chapter 3: Controller Parameter Descriptions

The MLS and CLS controllers let users modify the Proportional Band (PB), but they internally represent the PB as a Gain value.

• Range: 1 to 255.

• Heat/Cool: 35.

• Pulse: 20.

• Extruder Cool CH: 175.

Users edit the Proportional Band, but the controller uses a Gain value internally. This equation illustrates the relationship between the PB and Gain:

Derivative Term (1)

Integral Term (2)

Proportional Band =

For example, on a J-type thermocouple the high range is 1400 and low range is –350, so a gain of 35 gives a PB of 50 degrees. (The input type ranges are listed in the Input Type section and in the User’s Guide for your controller.)

This parameter contains the derivative term for PID output calculations. (The derivative term is also known as the TD or Rate.)

(High Range Value) – (Low Range Value)

Gain

• Range: 0 to 255 seconds.

• EX PROM: 125.

• Pulse Loop: 0.

• All Others: 0.

This parameter contains the integral term for PID output calculations. (The integral term is also known as the Reset or TI.)

• Range: 0 to 6000 seconds per repeat. (Setting the TI to 0 seconds

turns off the integral action.)

• STD Heat: 180.

• STD Cool: 60.

• Extruder: 500.

• Pulse: 0.

Communications Speciﬁcation 45

Chapter 3: Controller Parameter Descriptions

Input Type (3)

This parameter speciﬁes the input type.

• Range: 0 to 19 deﬁned values.

• Default: 1 (J-type thermocouple).

The following input types are currently deﬁned:

Decimal Number

0 Linear 00 –10 to 60 mV (scaleable) 1 J-type thermocouple 01 –350 to 1400°F

2 K-type thermocouple 02 –450 to 2500°F

3 T-type thermocouple 03 –450 to 750°F

4 S-type thermocouple 04 0 to 3200°F

5 R-type thermocouple 05 0 to 3210°F

6 B-type thermocouple 06 150 to 3200°F

7 Pulse Input (CLS, MLS, CAS) 07 0 to 2000 Hz 8 RTD1 (high resolution)

(Not available in CLS216/16CLS and CAS200/ CAS)

9 RTD2 (low resolution)

(Not available in CLS216/16CLS and CAS200/

CAS) 10 Skip Channel 0A N/A 11 to 13 Reserved for 8LS carbon potential N/A N/A 14 N/A N/A N/A 15 N/A N/A N/A 16 N/A N/A N/A 17 N/A N/A N/A 18 Nickel RTD

(Available in some MLS controllers) 19 Motor speed 13 –10 to 60 mV (scaleable) 20 E thermocouple 14 –328 to 1448°F

Description

Hex

Value

–212 to 760°C

–268 to 1371°C

–268 to 399°C

–18 to 1760°C

–18 to 1766°C

660 to 1760°C

08 –148 to 527°F

–100 to 275°C

09 –184 to 1544°F

–120 to 840°C

12 –940 to 572°F

–700 to 300°C

–200 to 787°C

Range

46 Communications Speciﬁcation

The input type determines the ranges for these other parameters:

• Process variable

• Setpoint

Chapter 3: Controller Parameter Descriptions

• Proportional band

• High process alarm

• Low process alarm

• Deviation band alarm

• Heat/cool spread

• Alarm deadband

Ranges for all input parameters are determined as follows:

• For thermocouple and RTD inputs, the high and low ranges are ﬁxed

at the values shown in the previous table.

• For pulse and linear inputs, the high and low ranges are determined

by the values entered for input scaling, as shown in the graph below.

High Range

High Process Variable

Output Type (4)

Low Process Variable

Low Range

–16.6% –10 mV

0% 0 mV

Low RDG

High RDG 100%

Sensor Input

This parameter deﬁnes the output type of a given output pin.

• Default: Heat outputs default to manual control, enabled, reverse

action, time proportioning. Cool outputs default to disabled, direct action, time proportioning.

• Range: A 1-byte value determined as shown in the tables below.

Bit Bit set to 0 Bit set to 1

0 and 1 See below 2 Loop is in automatic control Loop is in manual control 3 Autotune mode off Autotune mode on 4 Output disabled Output enabled 5 Spare Spare

60 mV

Communications Speciﬁcation 47

Chapter 3: Controller Parameter Descriptions

Bits 0 and 1 work together to determine some of the output’s characteristics:

Bit Bit set to 0 Bit set to 1

6 Output not set to Serial

DAC (see table below)

7 Output set to Reverse

action

Output set to Serial DAC (see table below)

Output set to Direct action

Setpoint (5)

Bit 6

Setting

0 0 0 Time Proportioning 0 0 1 DZC 0 1 0 Analog (only 8LS) 0 1 1 On/Off 100SDAC 1 0 1 3P DZC

Bit 1

Setting

Bit 0

Setting

Result

NOTE

Bit 2 in the heat output-type byte determines the loop’s control status (Automatic or Manual). The controller ignores Bit 2 in the cool output-type byte.

This parameter contains the process setpoint, expressed in engineering units. (The setpoint is affected by the Precision parameter.)

• The setpoint’s range depends on the loop’s input type.

• The default setpoint for a J-type thermocouple is 250 (25°F).

Process Variable (6)

Output Filter (7)

48 Communications Speciﬁcation

The process variable contains the compensated input measurement, expressed in engineering units. (This parameter is affected by the Precision parameter.)

• The process variable’s range depends on the loop’s input type

(described in the Input Type section).

The adjustable output ﬁlter dampens the control output response. (Setting the number of scans to 0 disables the ﬁlter.)

• Range: 0 to 255 scans.

• Default: 3 scans.

Output Value (8)

This parameter contains the output value, based on a full scale value of 32700 equals 100%. You can write to the output value at any time, but a write command is only meaningful for loops set to Manual control.

• Range: 0 to 32700 (0 to 100%).

• Default: 0.

High Process Alarm Setpoint (9)

The high process alarm setpoint is the absolute high process variable limit, expressed in engineering units. (This parameter is affected by the Precision parameter.)

• Range: –999 to 2500 (legal range determined by input type).

• Default: 10000 (1000°F) for a J-type thermocouple.

Chapter 3: Controller Parameter Descriptions

Low Process Alarm Setpoint (10)

The low process alarm setpoint is the absolute low process variable limit, expressed in engineering units. (This parameter is affected by the Precision parameter.)

• Range: –999 to 2500 (legal range determined by input type).

• Default: 0.

Deviation Alarm Band Value (11)

The deviation alarm band value indicates the amount of deviation from the setpoint before an alarm is issued. The amount of deviation is expressed in engineering units. (This parameter is affected by the Precision parameter.)

• Range: 0 to 255.

• Default: 5.

Alarm Deadband (12)

The alarm deadband prevents the alarm output from ﬂuctuating rapidly when the input is near the alarm setpoint. (This parameter is affected by the Precision parameter.)

• Range: 0 to 255.

• Default: 2.

Communications Speciﬁcation 49

Chapter 3: Controller Parameter Descriptions

NOTE

Process alarms, deviation alarms, and failed sensor alarms are set individually for each loop. They are controlled by bit settings in a number of alarm variables.

This section uses the following expressions interchangeably:

Bit set to 1

Bit set to 0 False Cleared

Users can set loop alarms to warn them of high and low process variables and high and low deviation from the setpoint. Users can also set a loop alarm deadband value that prevents alarm “chattering” in process and deviation alarms. (There are also failed sensor alarms for some input types; users cannot conﬁgure the failed sensor alarms.)

All of these alarms are individually indicated. They can also be individually enabled, disabled, and acknowledged. The host software can observe and set process alarm and deviation alarm values.

True Set

NOTE

Alarms in MLS and CLS controllers depend on these ﬁve 16-bit variables, all unsigned integers: Alarm_Status, Alarm_Mask, Alarm_Enable, Alarm_Control, Alarm_Acknowledge.

Each of these variables is responsible for a different alarm behavior, attribute, or condition. Each of the controller’s alarms has 1 bit in these variables; the table below shows the bit map for each variable. The bits are treated as 16 separate Boolean (TRUE/FALSE) variables.

Alarm_Status (13)

50 Communications Speciﬁcation

This parameter provides the current status of all the alarms for a loop, except for special ramp-soak alarms. When an alarm occurs, the controller sets the appropriate bit in Alarm_Status. When the alarm clears, the controller clears the bit for that alarm.

Chapter 3: Controller Parameter Descriptions

When using the Anafaze protocol, when an Alarm_Status bit has changed, and there are no higher–priority status codes to return, the controller will return an Ex (see the STS section in Chapter 1), in the high nibble of the next communications status byte it sends to the host software. The software should upload the Alarm_Status integers or words for all loops to determine which alarms have changed and in which loops.

Host software can read this parameter, but should not write to it.

NOTE

An alarm clears when its alarm condition is no longer present. If an alarm clears, and it has not already been acknowledged, it remains an unacknowledged alarm until the operator acknowledges it (by pressing the controller’s Alarm Ack key or through software).

Do not use host software to alter the status of the Alarm_Status bits.

When Alarm_Status Trips

An alarm trips only if the Alarm_Mask bit, Alarm_Enable bit, and the alarm condition are all TRUE. For example, the high process alarm trips if the Alarm_Mask bit and Alarm_Enable bit are all true, and the process exceeds the high process alarm setpoint value.

When Alarm_Status Clears

An alarm clears when the condition that caused it clears, or when the Alarm_Mask bit is set to FALSE. For example, the high process alarm clears if the process goes below the high process alarm setpoint.

Bit Alarm Name

0 Spare 1 Spare 2 Low deviation 3 High deviation 4 Low process 5 High process 6 T/C Reversed 7 T/C Short 8 T/C break (or open) 9 RTD open (not in 16CLS and CAS) 10 RTD short (not in 16CLS and CAS) 11 N/A 12 Ambient Warning (version 3.4 and later) 13 Ambient Cal Error

Communications Speciﬁcation 51

Chapter 3: Controller Parameter Descriptions

Bit Alarm Name

14 Full Scale Cal Error 15 Offset Cal Error

Ambient Sensor Readings (15)

This parameter returns the value of the system ambient sensor in degrees Fahrenheit to a tenth of a degree. (The ambient sensor is used for ambient temperature compensation for thermocouples.) Most Watlow Anafaze controllers have only one ambient sensor; only the MLS-32 has two. However, the block size has been allocated to allow a maximum of six ambient sensors per system.

Pulse Sample Time (16)

This parameter is the sample period in seconds for the pulse counter input. (The pulse input is available for the CLS, MLS, and CAS only.)

• Range: 1 to 20 seconds.

• Default: 1 second.

High Process Variable (17)

This parameter is one of four points used to scale inputs, expressed in engineering units. (This parameter is affected by the Precision parameter.)

• Range: –9999 to 30000.

• Default: 14000 (1400F) for J-type thermocouple.

Low Process Variable (18)

This parameter is one of four points used to scale inputs, expressed in engineering units. (This parameter is affected by the Precision parameter.)

• Range: –9999 to 30000.

• Default: –3500 (–350°F) for J-type thermocouple.

NOTE

Whenever the Input Type or Units are changed, the High Process Variable and Low Process Variable parameters are set to the default values for the Input Type. see Input Type (3) on page 46 for a list of these values.

52 Communications Speciﬁcation

Precision (19)

Chapter 3: Controller Parameter Descriptions

NOTE

Use the High Process Variable and Low Process Variable for an offset on all types of inputs. Add or Subtract the offset from both the High and Low Process Variables full scale valves. For example, for a J-type thermcouple, the full range is 14000 (1400°F) to –3500 (–350°F) with an offset of +5 degrees set the high Process Variable to 14050 and the low Process Variable to –3450, moving the full range scale up 5 degrees.

The precision determines the number of decimal places in the associated parameters.

The value stored in this parameter affects several other parameters.

• Range: –1 to +4.

• Default: –1 for a J-type thermocouple.

The MLS, CLS and CAS do not store any ﬂoating-point values. Instead, they use the Precision parameter to simulate ﬂoating-point calculations for these other parameters:

• Process variable

• Setpoint

• Proportional band

• High process alarm

• Low process alarm

• Deviation band alarm

• Heat/cool spread

• Alarm deadband

• Ready setpoint

• Segment setpoint

• Tolerance value

When the controller sends values for these parameters to host software, it sends them as integers. To convert the numbers to a decimal, the host software must do the following:

(1) Take the number from the controller.

(2) Divide it by 10

ting. So for example, if the precision is set to –1, divide values read via communications by 10, and if the precision is 2, divide by 100).

|p|

(where |p| is the absolute value of the precision set-

Communications Speciﬁcation 53

Chapter 3: Controller Parameter Descriptions

(3) If the original precision value (from the table below) was a negative

Exception

For the deviation band alarm, heat/cool spread, and alarm deadband parameters, follow the procedure above, but if the precision value from the table is negative, display the raw number read from the controller.

Display Format Menu

When users edit the controller’s Display Format menu for a linear input, they are really editing the precision for that input.

The next table shows the available precision values:

number, round the number to the nearest integer. Otherwise, display the number.

Precision

Value

–1 –999 to 3000 2556 257 0 –9999 to 30000 2556 2556 1 –999.9 to 3000.0 2556 255.6 2 –99.99 to 300.00 2556 25.56 3 –9.999 to 30.000 2556 2.556 4 –0.9999 to +3.0000 2556 0.2556

Display Format

Sample Raw Value Read

via Communications

Scaled

Display V alue

Cycle Time (20)

This parameter contains the time proportioning time base, expressed in seconds.

• Range: 0 to 255 seconds.

• Heat: 10.

• Cool: 3.

Zero Calibration (21)

This parameter returns the controller’s zero calibration counts.

Full Scale Calibration (22)

Digital Inputs (25)

54 Communications Speciﬁcation

This parameter returns the controller’s full scale calibration counts

This parameter returns the state of the controller’s digital inputs. If the input is an open circuit (high) the corresponding value returns a 1. If the input is connected to common or low a 0 is returned.

Chapter 3: Controller Parameter Descriptions

The Anafaze/AB protocol returns all 8 bits in 1 byte. See the table below.

Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Input 8 Input 7 Input 6 input 5 Input 4 Input 3 Input 2 Input 1

The Modbus-RTU protocol stores the states of the inputs in eight individually addressable discrete input registers.

Digital Outputs (26)

This parameter contains the state of the controller’s digital outputs. If the output is off (an open circuit), the value is 0. If the output is on, the value is 1. To turn on an output, set the corresponding bit to 1.

The Anafaze/AB protocol stores the states for up to eight outputs in 1 byte. So, a total of 5 bytes are required to store the states of the 35 digital outputs in a controller. See the table below to decode the bits.

• Default: 0 (off).

Byte 0 8 7 6 5 4 3 2 1 Byte 1 16 15 14 13 12 11 10 9 Byte 2 24 23 22 21 20 19 18 17 Byte 3 32 31 30 29 28 27 26 25 Byte 4 Not used 35 34 33

The Modbus-RTU protocol stores the states of the outputs in 35 individually addressable coil registers.

Override Digital Input (28)

This parameter enables the output override feature and selects a digital input to trigger it. When the feature is enabled and the speciﬁed input is activated, the controller sets all loops to manual mode at the heat and cool outputs at the levels speciﬁed by the Output Override parameters.

• Range: 0 to 8 (Disabled = 0, Enabled = 1 to 8, indicating the selected

digital input).

• Default: 0.

Override Polarity (29)

Bit 7Bit 6Bit 5 Bit 4Bit 3 Bit 2Bit 1Bit

Specify whether a low or high signal activates the output override feature.

• Range: 0 or 1 (Low = 0, High = 1).

• Default: 0.

Communications Speciﬁcation 55

Chapter 3: Controller Parameter Descriptions

System Status (30)

The system status command consists of internal registers that ﬂag hardware and software exceptions. The system status command takes 4 bytes. (None of the controllers use the last 2 bytes; they are reserved.)

Here is a bit map of the ﬁrst 2 system status bytes. More than 1 bit can be set at a time.

Bit 0 1

0 Battery OK Dead battery 1 Init Start OK Bad Init Start Bit 2 AIM OK AIM comm failure 3 No Ambient Error Ambient Error 4 No Ambient Warning Ambient Warning 5 Zero Calibration OK Bad zero calibration 6 Full scale calibration

value OK 7 Reserved 8 Alarms delay Off Alarms delay On 9-13 Reserved 14-15 See next table

Bad full scale calibration value

Here’s a partial bit map of system status byte 2. The CLS and CAS use bits 14 and 15 only.

Bit 15 Setting Bit 14 Setting Result

0 0 Controller has 4 loops 0 1 Controller has 8 loops 1 0 Controller has 16 loops

System Command Register (31)

The System Command Register is a register of mode and conﬁguration ﬂags for the controller’s processor.

• Default: 0.

Bit 0 1

0 Use default output data on

startup. 1 Operator keys enabled. Operator keys locked. 2 Unit set to 60 Hz. Unit set to 50 Hz. 3 Ramp-soak time base in hours

and minutes. 4 Alarm digital outputs active

Low.

Use memory data on startup.

Ramp-soak time base in minutes and seconds.

Alarm digital outputs active High

56 Communications Speciﬁcation

Bit 0 1

5 * Manufacturing Test 6 Parameter reset bit 7 Reserved * Warning: This may cause loss of data when used in normal

operation. Use only when these tests are absolutely necessary.

Data Changed Register (32)

The data changed register acts as a First-In-First-Out (FIFO) to point to parameters that have changed internally. The host software must query this register after receiving a “Data Changed” status ﬂag to determine which data has changed. (For more information about “Data Changed” status ﬂags, see the Status Byte section in Chapter 1.)

• Range: 0 to 255.

The general program ﬂow goes like this:

Chapter 3: Controller Parameter Descriptions

Input Units (33)

(1) If there is anything in the controller’s internal Data Changed Stack,

the controller returns a “Data Changed” status ﬂag. (See the Status Byte section in Chapter 1 for an explanation of the “Data Changed” status ﬂag.)

(2) The host receives a “Data Changed” ﬂag in the communications

packet.

(3) The host reads the Data Changed Register for the command number

of the parameter that changed and then uploads that data block.

(4) The controller notes that the Data Changed Register has been read

and waits for an Acknowledge from the host. When the Acknowledge has been received, the controller checks its own Data Changed Stack. If there are still data blocks that have been changed, but not uploaded, the controller puts the next command number in the Data Changed Register and continues to return a “Data Changed” status in communications packets. Otherwise, the Data Changed Register is cleared and no more Data Changed status ﬂags are returned. (For more help on this topic, see the Status Byte section in Chapter 1.)

MLS, CLS, and CAS show the process variable expressed in engineering units. This parameter consists of three character strings that provide text representation of the engineering units for each loop. (The default input units for a J-type thermocouple—the default input type— are in °F.)

For thermocouple and RTD inputs, the input units are preset; the third character of the loop’s string indicates whether the reading is in degrees Celsius (if the second and third characters are “°C”), or in degrees Fahrenheit (if the second and third characters are “°F”).

Communications Speciﬁcation 57

Chapter 3: Controller Parameter Descriptions

For linear and pulse inputs, users can select three characters to display. This table shows valid entries:

(Space) 32 20 #35 23

%37 25 /47 2F A to Z 65 to 90 41 to 5A 0 to 9 48 to 57 30 to 39

EPROM Version Code (34)

The ﬁrmware code for the EPROM version consists of 3 bytes. The ﬁrst one contains the controller/unit model (MLS, CLS, and CAS). The second one contains the EPROM major revision, and the third one contains the EPROM minor revision.

Character Decimal Value Hex Value

223 DF

WARNING

Options Register (35)

The next table shows EPROM model codes. (Other codes are reserved for older controllers.)

Code Model

9 MLS/MLS300 10 CLS/CL200 12 CAS/CAS200

Watlow Anafaze recommends that you do not write to the EPROM-version parameter.

The options register is register of ﬂags denoting ﬁrmware options in the controller. These options are currently deﬁned:

Bit 0 1

0 Reserved 1 Cascade option not present Cascade-enhanced

option 2 16-channel MLS 32-channel MLS 3 SmartWatch option not

present

SmartWatch option

58 Communications Speciﬁcation

Bit 0 1

4 Extruder option not present Extruder option 5 Ramp-soak not present Ramp-soak 6 Math package not present Math package 7 Reserved

Process Power Digital Input (36)

Enable the thermocouple short detection feature by selecting a digital input.

• Range: 0 to 8 (Disabled = 0, Enabled = 1 to 8 indicating the selected

digital input).

• Default: 0.

High Reading (37)

This parameter contains one of four points used to scale inputs. For thermocouple and RTD inputs, the high reading is expressed in tenths of a degree Celsius or Fahrenheit. For linear inputs, the high reading value is expressed in tenths (CLS) or hundredths (MLS) of a percent of full scale. For pulse inputs, the high reading value is expressed in Hertz.

Chapter 3: Controller Parameter Descriptions

• Range: –999 to 9999 (CLS), –9990 to 11000 (MLS).

• Default: 14000 (1400°F) for a J-type thermocouple.

Low Reading (38)

This parameter contains one of four points used to scale inputs. For thermocouple and RTD inputs, the low reading is expressed in tenths of a degree Celsius or Fahrenheit. For linear inputs, the low reading value is expressed in tenths (CLS) or hundredths (MLS) of a percent of full scale. For pulse inputs, the low reading value is expressed in Hertz.

• Range: –999 to 9999 (CLS), –9990 to 11000 (MLS).

• Default: –3500 (–350°F) for a J-type thermocouple.

NOTE

Note: Do not change High and Low Readings if the Input Type is NOT set to Linear or Pulse.

Heat/Cool Spread (39)

This parameter describes a deadband about the setpoint for heat/cool loops. The heat/cool spread is in units of the input variable. This parameter is affected by the Precision parameter.

Communications Speciﬁcation 59

Chapter 3: Controller Parameter Descriptions

• Range: 0 to 255.

• Default: 5.

Startup Alarm Delay (40)

This parameter designates a delay time for process and deviation alarms on power-up. The controller does not report process and deviation alarms for the speciﬁed number of minutes after the controller powers up.

The startup alarm delay is a global alarm parameter; it applies to all process and deviation alarms for every loop.

The startup alarm delay does not apply to failed-sensor alarms and AIM failure alarms.

• Range: 0 to 255 minutes.

• Default: 0.

High Process Alarm Output Number (41)

This parameter assigns the output number to which the high process alarm output is directed.

• Range: 0 to 34.

• Default: 0 (no high process alarm output).

Low Process Alarm Output Number (42)

This parameter assigns the output number to which the low process alarm output is directed.

• Range: 0 to 34.

• Default: 0 (no low process alarm output).

High Deviation Alarm Output Number (43)

This parameter assigns the output number to which the high deviation alarm output is directed.

• Range: 0 to 34.

• Default: 0 (no high deviation alarm output).

Low Deviation Alarm Output Number (44)

60 Communications Speciﬁcation

This parameter assigns the digital output number to which the low deviation alarm output is directed.

• Range: 0 to 34.

• Default: 0 (no low deviation alarm output).

Channel Proﬁle and Status (46)

In this byte, bits 0 to 4 hold the ramp-soak proﬁle number for the loop. Bits 5 to 7 hold the proﬁle’s status (Ready, Running, Hold, Trigger Wait, or Out of Tolerance).

• Range: See tables below.

• Default: 0.

Bits 0 to 4 hold the proﬁle number and reference letter:

Chapter 3: Controller Parameter Descriptions

Bit 4 Bit 3 Bit 2 Bit 1 Bit 0

00000 0 A 00001 1 B 00010 2 C 00011 3 D 00100 4 E 00101 5 F 00110 6 G 00111 7 H 01000 8 I 01001 9 J 01010 10 K 01011 11 L 01100 12 M 01101 13 N 01110 14 O 01111 15 P 10000 16 Q

Proﬁle

Number

Ref.

Letter

Bits 5, 6, and 7 hold the proﬁle status:

Bit 7 Bit 6 Bit 5 Status

000 0 0 1 Proﬁle is running “R”

010 0 1 1 Proﬁle in trigger wait state “W”

1 0 0 Proﬁle out of tolerance “O” 1 1 1 No proﬁle assigned

Proﬁle in Ready state

Proﬁle is holding

Communications Speciﬁcation 61

“S”

“H”

Chapter 3: Controller Parameter Descriptions

Current Segment (47)

This parameter returns the segment number that is currently executing. The controller’s front panel displays (current segment parameter value +1).

If the user has not assigned a ramp-soak proﬁle to the loop, this parameter is undeﬁned.

If the loop is in Ready state, this parameter has a value of –1. In Ready state, the controller’s front panel displays segment 0.

• Range: –1 to 19.

• Default: 0.

Segment Time Remaining (48)

If the time base is in minutes and seconds, this parameter holds the total remaining seconds, up to 999 minutes and 59 seconds. If the time base is in hours and minutes, this parameter holds the total remaining minutes, up to 999 hours, 59 minutes.

• Range: 0 to 59999.

• Default: 0.

Current Cycle Number (49)

This parameter returns the number of the current cycle. (Command 52, Number of Cycles, returns the total number of cycles to execute.)

• Range: 0 to 9999.

• Default: 0.

Tolerance Alarm Time (50)

The value of this parameter decrements once each time unit (each minute if the time base is set to hours and minutes, or each second if the time base is set to minutes and seconds), while the proﬁle is out of tolerance. When a ramp-soak segment is out of tolerance for longer than the tolerance alarm time, the controller goes into tolerance alarm and the tolerance timer resets.

• Range: 0 to 59999.

• Default: 0.

Last Segment (51)

62 Communications Speciﬁcation

This parameter denotes the last segment in the proﬁle.

• Range: 0 to 19.

• Default: 19.

Number of Cycles (52)

This parameter represents the total number of times to repeat the current proﬁle. Users can set 1 to 99 repeat cycle proﬁles or they can set the proﬁle to cycle continuously.

• Range: 0 (continuous), 1 to 99.

• Default: 1.

Ready Setpoint (53)

This parameter represents the ready segment’s setpoint. The ﬁrst segment begins ramping from the ready segment setpoint. When the proﬁle ends, the process returns to this setpoint. (This value is affected by precision.)

• Range: Low Process Variable to high Process Variable. (–999 to

• Default: 0.

Special logic applies to determining the decimal placement for the Ready Setpoint when using the Anafaze/AB protocol. When a proﬁle is assigned to a loop and the precision of the loop is greater than or equal to 0, the setpoint is divided by an additional factor of 10 when the precision is applied. When the proﬁle is assigned to a loop with precision –1, the precision is applied to the setpoint as usual (see Precision (19) on page 53).

Chapter 3: Controller Parameter Descriptions

9999, legal value determined by input type.)

For example, if a proﬁle with a Ready Setpoint of 1000 is assigned to a loop with its Input Type set to Linear and its Precision to 1, the resulting setpoint is 10. If the same proﬁle were assigned to a loop with Input Type set to J-type thermocouple (precision set to –1), the setpoint would be 100.

For the Modbus-RTU protocol, the setpoint is scaled by the precision setting only.

Ready Event States (54)

This parameter describes the ready segment’s output state for all outputs that are not used for control or for the SDAC clock. When the loop goes to the ready state, these outputs assume the state speciﬁed by this parameter.

• Range: 0 (off) or 1 (on).

• Default: 0 (off).

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Chapter 3: Controller Parameter Descriptions

In the Anafaze/AB protocol, the states are stored as bits in 5 bytes. Each bit listed in the table below represents an output from 1 to 34.

When accessed via the Modbus-RTU protocol, this parameter contains the ready segment event outputs for the ﬁrst 10 proﬁles (A to J) only. The state of each is stored in its own register. For access to all the ready segment events, see parameter 103.

Segment Setpoint (55)

This parameter represents the setpoint the process variable will reach at the end of the segment. (This value is affected by precision)

Bit 7Bit 6Bit 5Bit 4Bit 3Bit 2Bit 1Bit

0 Byte 0 8 7 6 5 4 3 2 1 Byte 1 16 15 14 13 12 11 10 9 Byte 2 24 23 22 21 20 19 18 17 Byte 3 32 31 30 29 28 27 26 25 Byte 4 Reserved 34 33

• Range: Low Process Variable to High Process Variable. (–999 to

9999, legal value determined by input type.)

• Default: 0.

Special logic applies to determining the decimal placement for the Segment Setpoint when using the Anafaze/AB protocol. When a proﬁle runs on a loop with a precision setting greater than or equal to 0, the setpoint is divided by an additional factor of 10 when the precision is applied. When the proﬁle runs on a loop with precision –1, the precision is applied to the setpoint as usual (see Precision (19) on page 53).

For example, if a proﬁle with a Segment Setpoint of 1000 runs on a loop with its Input Type set to Linear and its Precision to 1, the resulting setpoint is 10. If the same proﬁle runs on a loop with Input Type set to Jtype thermocouple (precision set to –1), the setpoint will be 100.

For the Modbus-RTU protocol, the setpoint is scaled by the precision setting only.

Triggers and Trigger States (56)

This byte holds the trigger input number, its active state, and its latch status. Triggers are saved in memory as indicated below.

Seg(1) Trig(1), Seg(1) Trig(2), Seg(2) Trig(1), Seg(2) Trig(2), etc.

64 Communications Speciﬁcation

• Range: 0 (no trigger), inputs 1 to 8.

Chapter 3: Controller Parameter Descriptions

• Default: 0 (no trigger assigned).

Bit Bit set to 0 Bit set to 1

0 to 3 See below 4 to 5 Reserved 6 Unlatched trigger (trigger

must remain true throughout the segment).

7 Active Off Active On

Bits 0 to 3 determine the input number for the trigger:

Latched trigger (trigger must be true at beginning of segment).

Bit 3 Bit 2 Bit 1 Bit 0

0 0 0 0 No trigger 00011 00102 00113 01004 01015 01106 01117 10008

Segment Events and Event States (57)

This parameter holds the event output number and event state for a proﬁle segment. Users can designate up to four events per segment; each event takes 1 byte. Events are saved in memory as indicated below.

Seg(1) Event(1), Seg(1) Event(2), Seg(1) Event(3), Seg(1) Event(4), Seg(2) Event(1), etc.

• Range: Outputs 1 to 34 (except outputs used for control or for the

SDAC clock).

• Default: 0 (no event assigned).

Here’s a bit map of the Event bytes:

Input

Number

Bit Bit set to 0 Bit set to 1

0 to 5 Determines the output number for an event 6 Reserved 7 Event is active Off Event is active On

Communications Speciﬁcation 65

Chapter 3: Controller Parameter Descriptions

Bits 0 to 5 determine the output number for an event:

Segment Time (58)

Result Bit 5

No events 0 0 0 0 0 0 Digital output 1 is an

event Digital output 2 is an

event Digital output 3 is an

event Digital outputs 4 to

33 are events Digital output 34 is

an event

000001

000010

000011

... ... ... ... ... ...

100010

Bit 4Bit 3Bit 2Bit 1Bit

This parameter represents the duration of a segment, in the time units selected elsewhere (hours and minutes or minutes and seconds).

• Range: 0 to 59999.

• Default: 0.

Tolerance (59)

The tolerance parameter represents an user-deﬁned allowable deviation from setpoint. If the process goes above a positive tolerance value or below a negative tolerance value, it is considered out of tolerance. See also Tolerance Alarm Time (50). This value is also affected by precision.

• Range: –99 to 99.

• Default: 0.

Ramp/Soak Flags (60)

This parameter is a byte register for each loop that has a ramp-soak proﬁle assigned to it.

Here’s a picture of this byte:

Bit Bit set to 0 Bit set to 1

0 The segment is within the toler-

ance time period.

1 * The segment does not require

alarm acknowledgment. (Segment may be out of tolerance but is not in tolerance alarm.)

2 Reserved

The segment is out of tolerance time period.

The user must acknowledge alarm. (Segment may be within tolerance.)

66 Communications Speciﬁcation

Output Limit (61)

Chapter 3: Controller Parameter Descriptions

Bit Bit set to 0 Bit set to 1

3 The proﬁle is in trigger wait

state 4 Reserved 5 Reserved 6 Reserved 7 Reserved

The controller toggles a bit in the data-changed register to notify high

level software that the alarm status has changed.

This parameter sets a limit on the output power percentage on either heat or cool outputs for any loop. The output limit works with the output limit time. While the limit is in effect, the output level will never exceed the speciﬁed limit.

The proﬁle is not in trigger wait state (remote hold)

• Range: 0 to 32700 (0 to 100%). Setting the limit to 100% (32700)

• Default: 32700 (100%), or disabled.

Output Limit Time (62)

This parameter describes the time span that the output limit is in effect.

• Range: 0 to 999 seconds. Setting the output limit time to 0 makes the

• Default: 0 seconds (continuous output limit).

The output limit only affects loops in automatic control (AUTO). The time-out period is restarted whenever:

• A loop switches from manual to automatic control.

• The controller restarts.

disables it.

output limit continuous; setting the output limit time from 1 to 999 seconds gives a range from 1 second to about 16 minutes.

Communications Speciﬁcation 67

Chapter 3: Controller Parameter Descriptions

Alarm_Control (63)

Setting a bit for an alarm in the Alarm_Control variable makes it a control alarm; clearing the bit makes it a standard alarm. This table explains the difference between standard alarms and control alarms.

Function Description

Alarm When an alarm condition occurs:

Control The alarm digital output activates on alarm and deacti-

The controller’s display changes to the loop that’s in alarm.

An alarm message ﬂashes on the display. The alarm’s digital output activates. The global alarm output activates. The operator must press the Alarm Ack key to stop the

ﬂashing message and deactivate the global alarm before the controller will accept other input from the keypad.

vates when the loop goes out of alarm. The global alarm output does not activate. Users do not have to acknowledge control alarms by

pressing the alarm Ack key.

Alarm_Acknowledge (64)

When an alarm occurs and it is not a control alarm, the corresponding Alarm_Acknowledge bit is set. Clearing the bit acknowledges the alarm.

Alarm_Mask (65)

When users turn alarms on or off from the front panel keypad, they are really setting or clearing the Alarm_Mask variable. (When an alarm is turned on, its Alarm_Mask bit is set.)

Setting Alarm_Mask to TRUE does not trip or clear alarms; instead, it lets the alarm checking routine check for them. The controller does not set or clear Alarm_Mask by itself; users edit this bit through the front panel keypad or in host software.

See the table on page 51 for alarm bits.

Alarm_Enable (66)

The Alarm_Enable variable is like the Alarm_Mask variable, except it is a temporary mask. An alarm will not trip until its Alarm_Enable bit becomes true and the following conditions are also met:

• The alarm condition occurs.

• The Alarm_Mask bit is set.

68 Communications Speciﬁcation

This variable is currently used for deviation and process alarms. Process alarms are automatically enabled at startup. If a deviation alarm is turned on (its Alarm_Mask bit is set), then the alarm is disabled until the process variable comes within the deviation range:

(PV ≤ SP + DEV - DB)

(PV

≥ SP - DEV + DB)

If the process variable is already in this range, the Alarm_Enable bit is immediately set.

See the table on page 51 for alarm bits.

Output Override Percentage (67)

When a sensor failure occurs and the loop is in Automatic mode, the loop switches to Manual mode at the output override percentage. If users have conﬁgured an output override digital input, they set every loop to the output override percentage when they change the polarity of the output override’s digital input to the active state.

Chapter 3: Controller Parameter Descriptions

AIM Fail Output (68)

• Range: 0 to 32700 (0 to 100%).

• Default: 0.

This parameter is valid for the MLS controller only. It designates a digital output for the MLS-AIM failure alarm. Setting this parameter to 0 disables it.

• Range: 0 to 34. (Setting this parameter to 0 disables the AIM fail out-

put.)

• Default: 0 (AIM fail output is disabled).

Communications Speciﬁcation 69

Chapter 3: Controller Parameter Descriptions

Output Linearity Curve (69)

This parameter lets users set heat and cool outputs to one of two nonlinear output curves, or to Linear (no curve).

100

Linear

Curve 1 Curve 2

SDAC Mode (70)

SDAC Low Value (71)

SDAC High Value (72)

• Range: Users can select 0 for no curve (linear), 1 for a slight curve,

and 2 for a more pronounced curve.

• Default: 0 (no curve).

This parameter toggles the SDAC between current and voltage output.

• Range: 0 to 1, where 0 = voltage and 1 = current.

• Default: 0.

This parameter sets a low range value for the output device. This value must be less than the SDAC high value.

• Range: 0 to 999 for voltage outputs and 0 to 1999 for milliamp out-

puts.

• Default: 000 (0.00 volts) or 400 (4.00 mA).

This parameter sets a high range value for the output device. This value must be greater than the SDAC low value.

70 Communications Speciﬁcation

• Range: 1 to 1000 for voltage outputs and 1 to 2000 for current out-

puts. (The controller displays this value with a ﬁxed decimal place, so the user sees a range of 1 to 10.00 for voltage inputs and 1 to

20.00 for current outputs.)

• Default: 1000 (10.00 volts) or 2000 (20.00 mA).

Save Setup to Job (73)

This parameter saves the current setup to one of eight jobs. It is used as a command; it is not used as data. When this parameter is set to a non– zero value, the current job is saved to that job number. The parameter is then immediately reset to zero. The job is only saved once, when the controller receives this command. To resave the job, resend the command.

• Range: 1 to 8.

• Default: 0 (no job).

Input Filter (74)

The adjustable input ﬁlter dampens the analog input response.

• Range: 0 to 255 scans. (Setting the number of scans to 0 disables the

• Default: 16CLS and 8CLS = 3 Scans (both are equal to 1 second),

Chapter 3: Controller Parameter Descriptions

ﬁlter.)

4CLS measurement = 6 Ambient = 0.

Loop Alarm Delay (75)

Delays process and failed sensor alarms for a loop until the alarm condition has been continuously present for longer than the speciﬁed alarm delay time.

• Range: 0 to 255.

• Default: 0 seconds (no loop alarm delay).

NOTE

MLS EPROMS prior to Version 2.30 do not support the loop alarm delay.

Loop Names (77)

This parameter assigns a two-character name to each loop for CLS, CLS2001, MLS and MLS300 controllers. For CAS and CLS200 see Channel Name (78).

• Range: 0 to 9, A to Z, °, /, %.

• Default: The loop’s number.

Communications Speciﬁcation 71

Chapter 3: Controller Parameter Descriptions

T/C Failure Detection Flags (78)

This parameter determines the thermocouple failure detection scheme for each loop in CLS, CLS2001, MLS and MLS300 controllers. The

following bits enable (bit set) or disable (bit cleared) the action.

0 Reversed thermocouple

1 Heat thermocouple break

2 Cool thermocouple break

3 to 7 Reserved

• Default: all bits cleared (i.e. all disabled).

Channel Name (78)

Bit Bit set to 0 Bit set to 1

Reversed thermocouple

detection disabled.

output averaging disabled.

detection enabled. Heat thermocouple break

output averaging enabled. Cool thermocouple break

output averaging enabled.

This parameter assigns an eight-character name to each channel in the CAS and CAS200. For the CLS, CLS200, MLS and MLS300, see Loop Names (77).

Restore PID Digital Input (79)

This parameter speciﬁes the digital input to restore the PID control from MAN mode to AUTO mode for each loop. When a thermocouple break occurs and the loop is in AUTO mode, the controller sets the loop to MAN mode. If the digital input is other than 0 and the input is low, the loop goes back to AUTO mode when the thermocouple-break condition clears.

• Range: 0 (none) to 8.

• Default: 0 (none).

Manufacturing Test (80)

This parameter is used for manufacturing to perform speciﬁc tests on each bit.

Bit Bit set to 0 Bit set to 1

0 Watchdog timer test disab led. Watchdog timer test

1 Halt mux scanning for calibra-

2 to 15 Reserved

tion test disabled.

enabled. Halt mux scanning for cali-

bration test enabled.

72 Communications Speciﬁcation

Chapter 3: Controller Parameter Descriptions

WARNING

This command should only be used when it is necessary to perform the above tests. Use of this command in normal operation can result in loss of data.

PV Retransmit Primary Loop Number (81)

This parameter speciﬁes the primary loop number for obtaining the process variable (PV) from the current loop or another loop. Setting this to 0 disables PV retransmit for the loop.

• Range: 0 (none) to MAX_CH.

• Default: 0 (none).

PV Retransmit Maximum Input (82)

This parameter speciﬁes the maximum Process Variable input allowed for PV retransmit calculation. This value must not be lower than the minimum input (command 84).

• Range: –999 to 9999 (depending on precision in primary loop).

• Default: 14000 (1400°F) for a J-type thermocouple.

PV Retransmit Maximum Output (83)

This parameter speciﬁes the maximum output (%) allowed for Procedss Variable retransmit calculation. Once speciﬁed, the output will not exceed this percentage. This number must not be lower than the minimum output (command 85).

• Range: 0 to 100.

• Default: 100%.

PV Retransmit Minimum Input (84)

This parameter speciﬁes the minimum PV input allowed for PV retransmit calculation. This number must not be higher than the maximum input (command 82).

• Range: –999 to 9999 (depending on precision in primary loop).

• Default: –3500 (-350°F) for J-type thermocouple.

Communications Speciﬁcation 73

Chapter 3: Controller Parameter Descriptions

PV Retransmit Minimum Output (85)

This parameter speciﬁes the minimum output (%) allowed for PV retransmit calculation. Once set, the output will not drop below this percentage. This number must not be higher than the maximum output (command 83).

• Range: 0 to 100.

• Default: 0%.

Cascade Primary Loop Number (86)

This parameter speciﬁes the cascade primary loop number to obtain the output values. This number cannot be the same as the current loop. Setting this to 0 disables the cascade feature for this loop.

• Range: 0 (none) to MAX_CH.

• Default: 0 (none).

Cascade Base Setpoint (87)

This parameter speciﬁes the setpoint used as an offset for each loop.

• Range: –999 to 9999 (depending on the precision in the primary

loop).

• Default: 250 (25°F) for a J-type thermocouple.

Cascade Minimum Setpoint (88)

This parameter speciﬁes the minimum allowable setpoint in the cascade calculation. The resulting setpoint will not go lower than this. This number must not be higher than the maximum setpoint (command 89).

• Range: –999 to 9999 (depending on the precision in the primary

loop).

• Default: 250 (25°F) for a J-type thermocouple.

Cascade Maximum Setpoint (89)

This parameter speciﬁes the maximum allowable setpoint in the cascade calculation. The resulting setpoint will not go higher than this. This number must not be lower than the minimum setpoint (command 88).

74 Communications Speciﬁcation

• Range: –999 to 9999 (depending on the precision in the primary

loop).

• Default: 250 (25°F) for a J-type thermocouple.

Chapter 3: Controller Parameter Descriptions

Cascade Heat/Cool Span (90)

This parameter is multiplied by the heat and cool outputs of the primary loop in the cascade calculation.

• Range: –9999 to 9999.

• Default: 0.

Ratio Control Master Loop Number (91)

This parameter speciﬁes the ratio control master loop number to obtain the process variable. This number cannot be the same as the current loop. Setting this to 0 disables the ratio control feature for this loop.

• Range: 0 (none) to MAX_CH.

• Default: 0 (none).

Ratio Control Minimum Setpoint (92)

This parameter speciﬁes the minimum allowable setpoint in the ratio control calculation. The resulting setpoint will not go lower than this. This number must not be higher than the maximum setpoint (command

89).

• Range: –999 to 9999 (depending on the precision in the master loop).

• Default: 250 (25°F) for a J-type thermocouple.

Ratio Control Maximum Setpoint (93)

This parameter speciﬁes the maximum allowable setpoint in the ratio control calculation. The resulting setpoint will not go higher than this. This number must not be lower than the minimum setpoint (command

88).

• Range: –999 to 9999 (depending on the precision in the master loop).

• Default: 250 (25°F) for a J-type thermocouple.

Ratio Control Control Ratio (94)

This parameter is multiplied by the master loop process variable in the ratio control calculation. These values are multiplied by 10 to retain 0.1 ratio precision.

• Range: 1 to 9999 (control ratio 0.1 to 999.9).

• Default: 10 (control ratio 1.0).

Ratio Control Setpoint Differential (95)

This parameter speciﬁes the setpoint used as an offset for each loop.

Communications Speciﬁcation 75

Chapter 3: Controller Parameter Descriptions

• Range: –999 to 9999 (depending on the precision in the master loop).

• Default: 0.

Loop Status (96)

This parameter speciﬁes a character status indicating if the loop is in manual or automatic mode. Autotuning and ramp-soak status are also included. The characters are identical to that shown on the controller’s bar display. This is an expansion of commands 4 and 46.

• Range: ‘A’ to ‘Z’ (uppercase letters), status are currently deﬁned as:

• Default: 77 (Manual).

65 = A = Automatic 77 = M = Manual 84 = T = Tuning 83 = S = Ramp/Soak Ready state (Start) 82 = R = Ramp/Soak Running 72 = H = Ramp/Soak Holding 87 = W = Ramp/Soak trigger Wait state 79 = O = Ramp/Soak Out of Tolerance

Output Type/Disable (97)

This parameter speciﬁes the output type (if not disabled) for the heat and cool outputs. Setting this to 255 indicates the output is disabled. Any other value indicates an enabled output. This is an expansion of command 4.

• Range: 0 to 255, output types are currently deﬁned as:

• Default:0 for heat outputs, 255 for cool outputs.

Output Reverse/Direct (98)

This parameter speciﬁes the heat and cool output control action as either Reverse or Direct. This is an expansion of command 4.

0 = Time Proportioning 1 = DZC 2 = Reserved 3 = On/Off 4 = SDAC 5 = 3P DZC 255 = Disabled

76 Communications Speciﬁcation

• Range: 0 or 1.

0 = Reverse 1 = Direct

• Default: 0 for heat outputs, 1 for cool outputs.

Controller Type (99)

This parameter speciﬁes the controller type. This is an expansion of command 30.

• Range: 0 to 3.

0 = Controller has 4 loops 1 = Controller has 8 loops 2 = Controller has 16 loops 3 = Controller has 32 loops

Ramp/Soak Proﬁle Number (100)

Chapter 3: Controller Parameter Descriptions

This parameter speciﬁes the assigned proﬁle number for each loop. Setting this to 255 indicates no proﬁle is assigned for that loop. This is an expansion of command 46.

• Range: 0 to 255.

• Default: 255 (no proﬁle assigned).

Reference letters are assigned as follows: 0 = A, 1 = B, 2 = C, etc.

Controller Address (101)

This parameter stores the controller’s network address. Changes to this parameter are effective the next time the controller powers up.

• Range: 1 to 247.

• Default: 1.

In the Anafaze/AB protocol, the controller responds to the address stored in this parameter plus 7. For example, if this parameter is set to 1 in a controller, that controller responds to messages with a DST byte value of 8 (1 plus 7).

Baud Rate (102)

This parameter stores the baud rate at which communications will operate. Changes to this parameter are effective the next time the controller powers up.

• Range: 0 to 2, with these rates available:

0 = 9600 1 = 2400

Communications Speciﬁcation 77

Chapter 3: Controller Parameter Descriptions

• Default: Varies by controller.

Ready Events (103)

This parameter is accessable using the Modbus-RTU protocol only. It describes the ready segment’s output states for all outputs that are not used for control or for the SDAC clock. When the loop goes to the ready state, these outputs assume the state speciﬁed by this parameter. The state of each is stored in its own register.

• Range: 0 (off) or 1 (on).

• Default: 0 (off).

2 = 19200

78 Communications Speciﬁcation

Appendix A: Communications Driver

Compiling and Linking

The driver is compiled and linked with any Microsoft™ compiler version 5.1 or later. This code is probably compatible with many other C compilers, but it has not been tested as such.

Include the ﬁle “def.h” in any module that contains calls to the driver. Calls are explained in the Commands section below. A sample program and makeﬁle have been included as a guide to using the communications driver.

Compatibility

Commands

The Anafaze Communications Driver is compatible with the CLS and MLS family of controllers. If you have a custom controller with custom data table values, you can change or add entries in the Set_Comm_Params() routine in “cmmd.c” to reﬂect the correct values.

The driver package consists of four commands:

• Init_Comm_Port()

• Close_Comm_Port()

• UpLoad()

• DownLoad()

This appendix covers only the usage of these commands. Setting up data, an interpreting status byte, etc., is covered in the Anafaze/AB Protocol chapter in this manual.

Init_Comm_Port()

Use Init_Comm_Port to open and initialize the comm port that is desired for communications.

BOOLEAN Init_Comm_Port(unsigned int com_port, BOOLEAN hi_baud, char error_check);

unsigned int com_port; This is either COM1 = 0, or COM2 = 1.

BOOLEAN hi_baud; Set TRUE for 9600 baud, or FALSE for

2400 baud.

Communications Speciﬁcation 79

Appendix A: Communications Driver

char error_check; Set to BCC, or CRC. BCC = 1. CRC = 2;

Example Call:

Init_Comm_Port(1, TRUE, BCC); Open COM2 for 9600 baud using Block Check Character(BCC).

Includes:

#include “def.h”

Return Values:

Returns TRUE if opening comm port was successful, or FALSE if attempt failed.

Close_Comm_Port()

Use this command to Release the comm port and interrupt associated with it.

void Close_Comm_Port(unsigned port);

unsigned port; This is either 0 or 1, depending on which

port is open.

Example Call:

Close_Comm_Port(1); Closes comm port 2 if open.

Includes:

#include “def.h”

DownLoad()

Use this command to download controller values.

char UpLoad(int ctlr_type, unsigned char ctlr_addr, unsigned char cmmd_num, int offset, int num_elements, void * write_addr, char sts);

int ctlr_type; TYPE_MLS16, TYPE_MLS32,

TYPE_CLS4, TYPE_CLS8, TYPE_CLS16.

unsigned char ctlr_addr; Controller address 0 to 31.

unsigned char cmmd_num; Command or parameter

number. See “def.h” for command deﬁnes.

int offset; Offset into array.

int num_elements; Number of array elements to

download.

80 Communications Speciﬁcation

void * write_addr; Starting address of data array.

Appendix A: Communications Driver

char sts; Controller status. See the Anafaze

Controller/Host InterfaceData and Communication Speciﬁcation manual.

Example Call:

return_value = DownLoad(TYPE_CLS8, 1, SETPT, 0, 8, sp); This call downloads 8 setpoints to an 8CLS with an address of 2.

Includes:

#include “def.h”

Return Value:

Returns: 1 if the download was successful. This what you

should normally get.

2 if the controller found an error in the download comm string. Sent NAK or negative acknowledge.

3 if the download was completely unsuccessful.

4 if the download was not completed because controller editing was in progress. Controller locked out any attempts to write.

UpLoad()

Use this command to upload controller values.

char UpLoad(int ctlr_type, unsigned char ctlr_addr, unsigned char cmmd_num, int offset, int num_elements, void * write_addr, char sts)

int ctlr_type; TYPE_MLS16, TYPE_MLS32,

TYPE_CLS4, TYPE_CLS8, TYPE_CLS16.

unsigned char ctlr_addr; Controller address 0 to 31.

unsigned char cmmd_num; Command or parameter

number. See “def.h” for command deﬁnes.

int offset; Offset into array.

int num_elements; Number of array elements to

download.

void * write_addr; Starting address of data array.

char sts; Controller status. See the Anafaze

Controller/Host InterfaceData and Communications Speciﬁcation manual.

Communications Speciﬁcation 81

Appendix A: Communications Driver

Example Call:

return_value = DownLoad(TYPE_CLS8, 1, SETPT, 0, 8, sp); This call Uploads 8 setpoints from an 8CLS with an address of 2.

Includes:

#include “def.h”

Return Value:

Returns: 1 if the upload was successful. This what

you should normally get.

2 if the controller found an error in the upload comm string. Sent NAK or negative acknowledge.

3 if the upload was completely unsuccessful.

82 Communications Speciﬁcation

Glossary

ACK (Acknowledge) A control code that signals that a syntactically correct

Address See Data table address and Device address.

AIM An analog input module for MLS controllers. Watlow Anafaze offers two

ASCII American Standard Code for Information Interchange. A code that

Baud rate The rate at which data is transmitted over a line, measured in bits per sec-

Glossary

message packet has been received.

different modules: AIM-16 and AIM-32.

assigns numeric values to characters.

ond.

BCC Block Check Character. A method of error checking for packets.

Binary numbers

Bit An abbreviation for binary digit. (A binary digit can have one of two dis-

Burst error An erroneous series of 1’s or 0’s in the communications bit stream.

Byte A group of eight bits.

Cleared, bit When a bit is “cleared,” it is set to False or 0. When a bit is “set,” it is set

CLS Compact Loop System. A Watlow Anafaze PID controller with 4, 8 or 16

CRC Cyclic Redundancy Check. A method of error checking for packets.

Numbers in base 2, where each digit has one or two distinct values (0 or

1).

tinct values, 0 or 1). A group of four bits makes up a nibble. A group of eight bits makes up a byte.

to True or 1.

loops.

Data table address

The logical address where data is located.

Communications Speciﬁcation 83

Glossary

Deadband, alarm

Derivative control action

Deviation alarm

The range through which a process variable must travel from the alarm setpoint toward the process setpoint before an alarm clears.

A control action in which the output value is proportional to the rate of change of the error between the process variable and setpoint.

The deviation alarm value is an absolute value that is always relative to the setpoint. The process is in Alarm in the following cases: Above (setpoint + deviation value) Below (setpoint – deviation value)

Device address The communications address assigned to the controller or host software.

DLE Data Line Escape. An escape code that signals that a control code follows

it.

Double-bit

An error in which two bits in a packet are incorrect.

error

Duplex, full Communications in which each node can simultaneously transmit and

receive.

ENQ Enquiry. A control code that the software sends to the controller, asking it

to resend the last ACK or NAK.

ETX End Text. A control code that signals the end of a transmission.

Gain The parameter that users can alter through host software to set the propor-

tional control action. The gain is a unitless number that is inversely proportional to the proportional band. (See also Proportional Band)

Hexadecimal numbers

Integral control action

Numbers in base 16 where each digit has one of 16 possible values (0 to F).

Control action in which the output is proportional to the time integral of the difference between the setpoint and process variable. (In other words, the rate of change of the output is proportional to the input.)

Job A set of operating conditions (setpoints, alarms, PID constants, etc.).

Linear input Watlow Anafaze controllers have an optional linear input type that allows

you to scale raw input readings to the engineering units of your process.

84 Communications Speciﬁcation

Glossary

LSB Least Signiﬁcant Byte. For all two-byte data types, the LSB is transmitted

before the MSB (Most Signiﬁcant Byte) in the packet.

MLS Modular Loop System. A Watlow Anafaze controller.

MSB Most Signiﬁcant Byte. For all two-byte data types, the MSB is transmit-

ted after the LSB (Less Signiﬁcant Byte) in the packet.

NAK Not Acknowledged. A control code that signals that a syntactically incor-

rect message packet has been received.

Nibble A group of four bits or half a byte.

Packet A packet consists of a sequence of bytes in a speciﬁc format; it can be as

large as 256 bytes of data. Information is exchanged between host software and the controller in packets.

Parity Error detection coding for serial communications. MLS, CLS and IRC2

controllers use no parity.

Precision parameter

Proportional Band (PB)

Proportional control action

Indicates the decimal format for controller parameters such as process variable, setpoint, etc.

The parameter that users alter from the front panel to set the proportional control action, expressed in engineering units of the process variable.

Control action with a continuous, linear relationship between the output value and the difference between the setpoint and the process variable.

Protocol A set of rules for the timing and format of messages in the network.

Pulse input An input for CLS controllers that measures a digital pulse signal.

Recipe See Job.

SDAC Serial Digital Analog Converter. A high-precision digital-to-analog con-

verter for control outputs.

Serial communications

Communications between a computer and another device (controller, for example). Watlow Anafaze hardware supports two formats: RS-232 for single device at short distances, and RS-485 for multiple devices at longer distances.

Communications Speciﬁcation 85

Glossary

Set, bit See Cleared, bit.

Single-bit

An error in which only one bit is incorrect.

error

Stop bit The last part of a character that assures that the next start element is rec-

ognized.

STX Start Text. A control code that signals the beginning of a transmission.

TI Time of Integral, or Reset. The parameter that users alter to set the inte-

gral control action, expressed in seconds per repeat.

TD Derivative term, or Rate. The parameter that users alter to set the deriva-

tive control action, expressed in seconds.

86 Communications Speciﬁcation

Watlow CLS200, MLS300, CAS200 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

Contents

Overview

In This Manual

Chapter 1: ANAFAZE/AB Protocol

Protocol Syntax

Control Codes

Transaction Sequence

Packet Format

Sending Control Codes

Codes in a Packet

Sending a DLE as Data

DLE STX

STS (The Status Byte)

TNSL

TNSH

ADDL

ADDH

DATA

DLE ETX

Error Checking

Block Check Character (BCC)

BCC or CRC

Cyclic Redundancy Check (CRC)

Examples

Block Read

Block Write

Message Data

Data for a Read Command

Data for a Write Command

Two-Byte Data Types

Figuring Block Size

Anafaze/AB Data Table Summary

Ordering of Heat and Cool Channel Parameters

Anafaze/AB Protocol Data Table

Chapter 2: Modbus-RTU Protocol

Overview

Transactions on Modbus-RTU Networks

The Query-Response Cycle

The Query

The Response

Serial Transmission

Coding System

Bits per Byte

Message Framing

Error Check Field

Handling the Address Field

Handling the Function Field

Contents of the Data Field

Contents of the Error Checking Field

How Characters are Transmitted Serially

CRC Error Checking

Function Codes

x01 Read Coil Status

x02 Read Input Status

x03 Read Holding Registers

x04 Read Input Registers

x05 Force Single Coil

x06 Preset Single Register

x08 Diagnostics

Diagnostic Subfunctions

x00 Return Query Data

x01 Restart Communications Option

x02 Return Diagnostic Register

x04 Force Listen Only Mode

x0A Clear Counters

x0B Return Bus Message Count

x0C Return Bus Communication Error Count

x0D Return Bus Exception Error Count

x0E Return Slave Message Count

x0F Return Slave No Response Count

x0F Force Multiple Coils

x10 Preset Multiple registers

Writing Data

Reading Data

Examples

Read Examples