Rockwell Automation 1772-AF3, D17726.5.2 User Manual

Auxiliary Function PROM
(Cat. No. 1772AF3)
for the Mini-PLC-2/15 Controller

User Manual

Table of Contents

Introduction 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

General 11. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Purpose
Audience 12
Programs
Extended Data Comparison 12
Functions 13

Installation/Removal Precautions 21. . . . . . . . . . . . . . . . . . .

General 21. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Installation 21
Removal 23

File Search Instruction 31. . . . . . . . . . . . . . . . . . . . . . . . . . . .

General 31. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Programming the File Search Instruction 31
Enabling
Function
Instruction Execution Time 37
Response To Errors in UserEntered Data 37
Example Programs 37

of This Publication

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

fo Implementing Machine Diagnostics

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

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

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

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

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

the Instruction
of Control Bits

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

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

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

12. . . . . . . . . . . . . . . . . . . . . . . . . . . . .

12. . . . . . . . . . . . . .

35. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

36. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

File Diagnostic Instruction 41. . . . . . . . . . . . . . . . . . . . . . . . .

General 41. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

Programming
Enabling
Function
Instruction Execution Time 48
Response To Errors in UserEntered Data 48
Example Programs 49

the File Diagnostic Instruction
the Instruction
of Control Bits

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

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

42. . . . . . . . . . . . . . . . .

47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

47. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

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

Programming Check List 51. . . . . . . . . . . . . . . . . . . . . . . . . .

General 51. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

AF3 Recommendations & Precautions A1. . . . . . . . . . . . . . . .

AF3 PROM Handling Recommendations and Precautions A1. . . . . . .

Introduction

Chapter

1

General

The Auxiliary Function PROM (cat. no. 1772-AF3) lets you expand the
instruction set of your Mini-PLC-2/15 controller to include the file search and
file diagnostic instructions. These instructions are functionally similar to their
counterparts in the PLC-2/30 controller but their user-entered instruction format
is different.

For simplification throughout this manual we refer to the Auxiliary Function
PROM (cat. no. 1772-AF3) as the AF3 PROM.

You can use the AF3 PROM only with the Mini-PLC-2/15 processor module
(cat. no. 1772-LV) series A revision 11 or later, and series B revision 4; and
with the Industrial Terminal (cat. no. 1770-T3) (Table 1.A).

Table 1.A
AF3

PROM Response Controller

MiniPLC2/15 Controller User Program 2K Words

Series Revision Read Write Erase

A 6 and later Yes No No

[1]

B all Ye s Yes No

[1]

You can erase the 2K memory portion of the AF3 with ultraviolet light. However, the 2K memory for file

search and file diagnostic functions would be irretrievably lost.

The AF3 PROM has a 2K (16 bit) word memory into which you can transfer
your ladder diagram program (for backup memory), and a 2K word memory for
the file search and file diagnostic functions. You can transfer your program into
the AF3 PROM with series B controllers but not with series A controllers
(NO TAG). Mini-PLC-2/15 Processor EPROM (publication 1770-915)
describes how you transfer your program to the backup PROM.

NOTE: The AF1 is sensitive to ultraviolet light, therefore when exposed to uv
light, both the program and the auxiliary functions are erased. The AF1’s
transparent window is covered with the product label to avoid accidental
alteration of memory from uv light sources. Do not remove this label.

11

Chapter 1

Introduction

Purpose of This Publication

Audience

Programs fo Implementing
Machine Diagnostics

This publication shows you how to install and use the AF3 PROM in your
Mini-PLC-2/15 controller.

We assume that you are familiar with programming and operation of the
Mini-PLC-2/15 controller and the Industrial Terminal (cat. no. 1770-T3). We
also assume that you are familiar with files and file instructions.

WARNING: : Use only Allen-Bradley authorized programming
devices to program Allen-Bradley programmable controllers.
Using unauthorized programming devices may result in
unexpected operation, possibly causing equipment damage
and/or injury to personnel.

Programs for machine diagnostics minimize machine downtime and
maintenance time. Troubleshooting time is also reduced by isolating failed
machine components and devices. In cases where devices are direct inputs to
the PC, such as mechanical components, diagnostic programs can be used to
isolate problem areas by monitoring various critical machine or process
parameters. Diagnostic routines can even warn of potential failures so that
preventive maintenance can be performed at a convenient or scheduled time
before the failure occurs. Machine failures can also be recorded by the PC to
provide historical failure/reliability trend information.

Extended Data Comparison

12

All machine failures and malfunctions detected by the PC can be displayed
directly by several methods. Fault code numbers related to specific faults can
be displayed on an LED display, or alphanumeric messages can be displayed on
a CRT or printer to describe the faulted device or malfunction.

There are several methods commonly used to implement machine diagnostics.
One method is referred to as extended data comparison (EDC). This diagnostic
method is a useful technique for automatically detecting an out of sequence or
faulted I/O device. EDC can be summarized as follows: At each step in a
particular sequence or operation, a word containing the actual I/O status is
compared to a desired or standard I/O status word. If the machine or process is
operating properly, the bit pattern of the actual I/O word will be identical to the
bit pattern of the desired I/O status word.

Should an input fail, or be out of sequence, the bit patterns would differ, and
your program would initiate a routine that would determine which bit of the
input word represented a faulted input. the basic EDC concept is normally
expanded to include a group or file of input words and a corresponding file of
desired standard words. By comparison with a standard, each input is checked

Chapter 1

Introduction

for its proper bit status at a particular step or operation. The desired standard
files can be loaded automatically by a process called a teach routine (described
in the application note PLC-2/30 Diagnostics available from PC Systems
Division, Application Engineering Department).

Program routines for EDC are very similar to a sequencer instruction that
compares a file of input words with a file of standard words for a desired status
at each particular step. Therefore, the routine should only be implemented on a
sequential machine or operation. Keep in mind that the I/O must be at a static
stage for the comparison to be valid. Dynamic I/O or asynchronous machining
operations would result in invalid I/O fault detection.

Functions

The AF3 PROM performs the following functions:

File Search - This instruction locates all words in a file whose data is

identical to the data of a specified word.

File Diagnostic - This instruction is used to locate discrepancies between

actual and desired states of I/O or data table words on a bit by bit basis.

13

Chapter

2

Installation/Removal Precautions

General

Installation

The AF3 PROM can be damaged during routine handling if proper precautions
are not taken to reduce static electricity discharges. Refer to appendix A for
recommended handling and handling precautions.

You must take special car in handling the AF3 PROM to ensure the pins do not
get bent or contaminated. Bent or contaminated pins can prevent proper AF3
PROM operation and use. Store the AF3 PROM in its shipping container. Also,
the AF3 PROM transparent window is covered with the product label to avoid
accidental alteration of memory from ultraviolet light sources. Do not remove
this label.

The AF3 PROM fits into a 28-pin ZIF (zero insertion force) socket, which is
located under a hinged door at the lower side of the Mini-PLC-2/15 processor
(Figure 2.1).

Figure 2.1
PROM

Socket

10715I

21

Chapter 2

Installation/Removal Precautions

The position of the notch on the AF3 PROM, when installed, must correspond
to the position of the notch shown on the label (Figure 2.2).

Figure 2.2
AF3

Installed

PROM Installation

PROM
Notch

Lock

OFF

UP

1772AF3

DO NOT

ERASE

ON

Release

11590

To install the AF3 PROM, perform the following steps:

1. Turn the mode select switch to PROG position.

2. To maintain processor memory contents, connect an external battery pack

(Figure 2.3) to the processor with the Mini-Processor Transport Cable (cat.
no. 1772-CD).

Figure 2.3
External

Battery Backup

MiniPLC2/15 Processor

(Cat. No. 1772LV)

MiniProcessor
Transport Cable

(Cat. No. 1772CD)

Battery Pack

(Cat. No. 1771BB)

11182

3. Remove AC power from the I/O chassis.

22

4. Remove the processor module from the I/O chassis.

5. Check all AF3 PROM pins to ensure they are not bent or contaminated.

Chapter 2

Installation/Removal Precautions

6. Loosen the screw and lift the PROM door (Figure 2.1).

7. Push the ON tab toward the center to unlock the 28-pin ZIF socket.

8. Remove the PROM if there is one in the socket.

9. Position the AF3 PROM so its notch and arrow face the OFF tab as shown

in figure 2.2.

10.Carefully align all pins with their respective sockets. Gently seat the AF3

PROM by pushing it down into its socket. Misaligned pins can bend and
miss their sockets.

11. Lock the AF3 PROM in place by pushing the OFF tab toward the center.

12.Close the PROM door and tighten the screw.

13.Install the processor module into the I/O chassis.

Removal

14.Connect AC power to the I/O chassis power supply.

15.Disconnect the external battery pack (Figure 2.3) from the processor along

with the mini-processor transport cable.

16.This completes the installation of the AF3 PROM into the Mini-PLC-2/15

controller.

To remove the AF3 PROM, perform steps 1 thru 8 of how to install the AF3
PROM. Then perform steps 12 thru 16.

23

File Search Instruction

Chapter

3

General

The auxiliary file search instruction is an output instruction. It searches a file
looking for a match of data contained in any file word with data of a specified
match word. The instruction starts at the beginning of the file and searches
from lowest to highest word address (lowest to highest position number) and
from lowest to highest bit number. When the instruction finds a match, it
simultaneously stores the position of the file word (3-digit BCD number) and
sets the true bit. The true bit signals that the instruction found a match. Your
program logic can detect the setting of the true bit and perform the application
logic associated with the match.

Your program must cycle the instruction’s enable bit through a false-to-true
transition for each match of file data, until the instruction sets its done bit. The
instruction sets a done bit after it finds the last match in the file or if it finds no
match in the file. In the next false-to-true transition of the enable bit,
instruction clears the stored position number, and resets the instruction’s control
bits. If your program has cycled the enable bit, the instruction will immediately
begin the search again from the beginning of the file.

Generally, a minimum of two scans is required to detect each match. In the first
scan the instruction is enabled, it finds the match, stores the position number of
the matched word, and sets the true bit. In the next scan, the instruction resets
the true bit, and your program can reset the enable bit. Later in this chapter we
will describe a program that detects a match on each scan.

Programming the File Search
Instruction

You enter the file search instruction into program logic by pressing the key
sequence [SHIFT][EAF] 21 on the industrial terminal keyboard (series B or
later), or [SHIFT][SCT] 21 on the keyboard of an earlier model that does not
contain the [EAF] key. The instruction will appear as shown in Figure 3.1.

Enter the data address and result address into the instruction block as octal
(BCD) numbers from 0020 thru 3577. Typically, choose addresses from middle
to upper sections of the data table. A data address of 0400 and result address of
0406 are typical (Figure 3.2).

31

Chapter 3

File Search Instruction

Figure 3.1
Auxiliary

Numbers shown are default values and must be replaced
by your values. The number of default address digits
originally displayed, 3 or 4, depends on the size of the
data table.

Function Format

Figure 3.2
Example File Search Instruction

Execute Aux

Function

Funtion Number:
Data Addr:
Rresult Addr:

Execute Aux

Function

Funtion Number:
Data Addr:
Rresult Addr:

01
010
010

21
0400
0405

Next, you will learn how to load data into addresses of the instruction.

You can load values into their respective addresses using the data monitor bit
manipulation mode of the industrial terminal. Press the key sequence
[SEARCH] [5] [3] followed by the word address. The industrial terminal will
display the 16 bits of the word address you entered. Then you enter the binary
equivalent of the values, one bit at a time (Figure 3.3).

Figure 3.3
Example

Word Bit Location

Location 17 16 15 14 13 12 11 10 07 06 05 04 03 02 01 00 Description

0400 Nor used 0 0 0 0 0 0 0 1 0 0 0 0 File Length = 10 words

0401 Available for 0 1 0 0 0 0 0 1 0 0 0 0 Address of File, lower 3 digits,

0402 Bit Storage 0 0 0 0 0 0 0 0 0 0 0 0 Address of File, upper 3

0403 Application Dependent Data of match word

of UserEntered Data (Binary)

410

digits, 000

32