B&B Electronics 232DRIO User Manual

RS-232 Digital Relay I/O

Model 232DRIO

Documentation Number 232DRIO1005

Designed and Manufactured

of domestic and imported parts by

B&B Electronics Mfg. Co. Inc.

707 Dayton Road -- P.O. Box 1040 -- Ottawa, IL 61350

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http://www.bb-elec.com

[e-mail]

© B&B Electronics – January 2008

pn#4520-r2

This product

In Ottawa, Illinois

USA

Internet:

[e-mail]

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Table of Contents

Chapter 1- Introduction ........................................... 3

232DRIO Features .................................................. 3

Packing List ............................................................. 2

232DRIO Specifications...........................................

Opto-Isolated Input ................................................................ 3

Relay Outputs ....................................................................... 3

Power Supply ........................................................................ 3

Communications ................................................................... 3

Environment .......................................................................... 3

Size ....................................................................................... 3

Chapter 2 - Connections ......................................... 5

I/O Connections ............................................ ………5

Opto-isolated Input ................................................................ 5

Relay Outputs ....................................................................... 5

Ground .................................................................................. 5

Serial Port Connections ........................................... 6

Power Supply Connections ...................................... 7

Chapter 3 - Commands ........................................... 9

Syntax ................................................................... 10

I/O Data Bytes ..................................................................... 11

Read I/O Lines Command ..................................... 13

Set Output Lines Command .................................. 13

3

Chapter 4 - I/O Interfacing ..................................... 15

Opto-isolated Input ................................................ 15

Relay Outputs ........................................................ 17

Chapter 5 - Software .............................................. 19

Programming Techniques ...................................... 19

Opening a COM Port........................................................... 19

Closing a COM Port ............................................................ 19

QuickBasic .......................................................................... 20

Read I/O States Command ................................................. 20

Set Output States Command .............................................. 20

C/C++ .................................................................................. 21

Read I/O States Command ................................................. 21

Set Output States Command .............................................. 21

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Demonstration Program ........................................ 22

Hard Drive Installation ......................................................... 22

Running Demonstration Program ....................................... 22

APPENDIX A .......................................................... A-1

ASCII Character Codes ........................................ A-1

APPENDIX B .......................................................... B-1

Hexadecimal/Decimal Conversions ...................... B-1

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Chapter 1- Introduction

232DRIO Features

The 232DRIO is a general purpose data acquistion controller that
is connected to your computer’s RS-232 serial port. The 232DRIO
offers 1 opto-isolated input and 2 relay outputs. With these features,
the controller can be used to sense external ON/OFF conditions and
to control a variety of devices.
The relay outputs are CMOS/TTL compatible. The optically
isolated AC/DC input are also CMOS/TTL compatible. For
maximum flexibility, both input and outputs are connected with
internal screw type terminal blocks. Three LEDs are provided to
monitor the status of each of these.
The 232DRIO connects to your computer’s RS-232 serial port
through a DB-9F connector. The unit communicates at a baud rate
of 9600, 8 data bits, no parity, and 1 stop bit. This unit can not be
powered through the handshake lines because of the higher current
requirement to drive the relays. However, the unit may be powered
by an external +12Vdc source brought in through the power pin, pin
#9 of the serial port. If the 232DRIO cannot be powered using the
previous method, it may be powered with +12Vdc @ 100mA through
the supplied terminal blocks. Power supply is available.

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Figure 1.1 – 232DRIO Module

Serial Port
DB-9S

TD

RD

5-30 Vdc/Vac

Input

RS-232

Transceiver

+5V

R

Opto
Isolator

POWER

SPDT

RELAY

Microcontroller

SPDT

RELAY

GND
+12Vdc

#2 N/O
#2 N/C

#2 Com

#1 N/O

#1 N/C
#1 Com

Figure 1.2 – Simplified Block Diagram

Packing List

Examine the shipping carton and contents for physical damage.
The following items should be in the shipping carton:

1. 232DRIO unit

2. Software

3. This instruction manual
If any of these items are damaged or missing contact B&B
Electronics immediately.

232DRIO Specifications

Non-polarized, Optically Isolated Input

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Number of Channels: 1
Indication Mode
Logic “0”: LED on, digital voltage input high
Logic “1”: LED off, digital voltage input low
Input Electrical Characteristic
Voltage input low: <1.5 VAC/VDC
Voltage input high: 5-30 VAC/VDC @ 1mA to 30mA
Isolation Voltage: 2500 V
Leakage Current: 10 µA max.

Relay Outputs

Number of Channels: 2 electromechanical relays
Factory Default: Both relays de-energized

Indication Mode
Logic “0”: LED off, Relays de-energized
Logic “1”: LED on, Relays energized
Relay Ratings
Contact (standard): 10A @ 120VAC

8A @ 30VDC (resistive)
Max. switching capacity: 1200VA/240W
Max. operating voltage: 250VAC/125VDC

Max. carrying current: 10A (AC), 8A (DC) – standard

Min. permissible load: 100 mA @ 5 VDC
Relay Form: Form C, single-pole double-throw
(SPDT)
Output Terminals: Normally open (N/O) or
Normally close (N/C)
Relay Life (mech.): 10 million operations min.
Relay Life (load dependent): 100 thousand operations min.
Operating Time: 10 msec. max. (mean: ~5.1ms)

Power Supply
Input Voltage: 9-16 VDC

Input Current: 100 mA
Connections: Blue terminal block field wiring
Pin #9 (Power pin) of DB9F

Communications
Standard: RS-232 (unit is DCE)

Baud Rate: 9600
Format: 8 data bits, 1 stop bit, no parity

Environment
Operating Temperature: 0°-70°C

Operating Humidity: 0-95%, non-condensing

Storage Temperature: -20°-70°C
Size 4.60”L x 2.40"W x 1.32"H

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Chapter 2 - Connections

Do not make any connections to the 232DRIO until you have
read this chapter. Remember to power down the unit and any

other connected devices before making any kinds of connections.
Also be sure that the wires connected to the terminal blocks will
support the voltage and current requirements of your external
devices.

This chapter will cover the connections for the 232DRIO. There
are four sets of connections: opto-isolated input (optional), relay
outputs, serial port, and power supply.

I/O Connections

Connections to the I/O lines are made through the internal block
terminals. These should clearly be labeled on the board. Refer to
Table 2.1. See Chapter 5 for I/O interfacing examples.

Opto-isolated Input (black terminal blocks)

The non-polarized, opto-isolated input line is CMOS/TTL
compatible and can handle voltages from 0Vdc/Vac to +30Vdc/Vac.
Refer to the Specification for a complete detail.

Relay Outputs (blue terminal blocks)

The relay output lines have a maximum operating voltage of
+250Vac/+125Vdc and are CMOS/TTL compatible. Refer to the
Specification for a complete detail. Both relays are de-energized

at factory default settings.
Ground

Connect the ground correspondingly as marked. Do not
interchange the grounds for input and power. Otherwise, the input
will not be optically isolated. The input is non-polarized so the input
ground could be connected to either one of the black terminal while
the power ground must be connected as marked on the blue
terminal.

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Table 2.1 - 232DRIO Terminal Blocks

Blue
Pin # Function

1 - Ground Input Power 1 Opto-Isolated Input
2 +12Vdc Input Power 2 Opto-Isolated Input
3 #2 N/C-Normally Closed Non-polarized
4 #2 N/O-Normally Opened 0-30 Vdc/Vac
5 #2 C-Common
6 #1 C-Common
7 #1 N/C-Normally Closed
8 #1 N/O-Normally Opened

Black
Pin #

Function

Serial Port Connections

In order to communicate to the 232DRIO module it must be
connected to an RS-232 serial port. The unit is designed for a baud
rate of 9600, so the serial port must be set for this rate. A data
format of 8 data bits, 1 stop bit and no parity is used.
is configured as a DCE device (See Table 2.2). If your
communications equipment is configured as a DTE device, such as
a standard IBM PC serial port, the 232DRIO should be connected
using a “straight through” DB-25 cable or a standard DB-9 to DB-25
cable adapter as shown in Table 2.3. If your communications
equipment is configured as a DCE device, such as a modem, the
232DRIO should be connected using a “null modem” cable (see
Table 2.4).

The 232DRIO

Table 2.2 – RS232 Connector Pinout

DB-9S
Pin #

2 Receive Data (RD) Output Required
3 Transmit Data (TD) Input Required
5 Signal Ground (SG) ------ Required
9 Power pin Input Can be wired to

Signal

Signal
Direction at
232DRIO

Notes

power unit

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Table 2.3 – 232DRIO To DTE Connections

232DRIO
Pin #

2 Receive Data (RD) 3 2
3 Transmit Data (TD) 2 3
5 Signal Ground (SG) 7 5
9 Ring Indicator 22 9

Table 2.4 – 232DRIO To DCE Connections

232DRIO
Pin #

2 Receive Data (RD) 2 3
3 Transmit Data (TD) 3 2
5 Signal Ground (SG) 7 5
9 Ring Indicator 22 9

Signal

Signal

DTE DB-25
Connection

DCE DB-25
Connection

DTE DB-9
Connection

DCE DB-9
Connection

Power Supply Connections

The power requirement is 12VDC at 100mA. Power to the
232DRIO can be wired through the RS-232 serial port pin #9 (power
pin) or by an external power supply through the blue terminal blocks.
Serial ports can not provide enough power to supply the 232DRIO’s
100 milliamp requirement.

Chapter 3 - Commands

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There are only two basic commands required to control the
232DRIO: set output lines and read I/O lines. For normal
environments, command strings are from three to four bytes in
length; the “!” character, the “0” (zero) character, one command
character, and one data byte (if required).

With serial communications in a laboratory environment, the
possibility of a communication error occurring is minimal. However,
in a harsh or an industrial environment the possibility increases. A
communication error occurs when a bit transmitted as a “1” is
received as a “0” or vice versa. If the 232DRIO receives a error in
one or more of the first three command characters (“!0X”), the unit
will not execute the command. However, if the 232DRIO receives a
communication error on a data byte (I/O byte for Read Digital
command or state byte for Set Output State command), the
command will be executed since the unit has no way of knowing that
there was an error.

To provide the 232DRIO with a way of detecting errors in the
data fields, an additional set of commands can be used. This set of
commands begins with the “#” (23h) character, instead of the “!”
(21h) character. Refer to Table 3.1. With these commands every
data byte that is transmitted or received is followed by it’s
complement. For example, to read I/O lines:

Command syntax:

#0R

Response syntax:

{DATA}{~DATA}

Where “~” is used to indicate the “complement of.” If DATA has
a reading of 1, the following would be received:

{01}{FE}

Where FEh is the complement of 1. The complement of number
“x” can be calculated in QuickBasic as follows:

comp = (NOT x) AND &HFF

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Function Command Response

Set Output Lines !0S{…} No response
Read I/O Lines !0R {…}
Set Output Lines #0S{…}{~…} No response
Read I/O Lines #0R {…}{~…}
Symbol: {…} represents one byte
<…> represents a numeric value
~ complement of the specified data byte

Before going into the specifics of each command, it is important
to understand that a byte has a numeric value from 0 to 255. The
byte's value can be represented in decimal (0 -255) format,
hexadecimal (00 - FF) format, binary (00000000 - 11111111) format
or as an ASCII character. The fixed bytes of each command will be
represented as ASCII characters, for example: “!0R”. Refer to
Table 3.1. However, it is important to remember that an ASCII
character has a numeric value. Example: the ASCII “0” (zero) does
not have a value of zero but has a value of 48. The decimal and
hexadecimal equivalents of some ASCII characters are shown in
Table 3.2. Some commands require an additional data byte to
complete the command. These data bytes may be represented in
any of the formats listed above. Refer to Appendix A for more ASCII
and decimal equivalents.

Table 3.1 – 232DRIO Commands

Table 3.2 – Equivalent Values

ASCII Decimal Hexadecimal

! 33 21h
# 35 23h
0 48 30h

R 82 52h
S 83 53h

Syntax

Command strings consists of three to five bytes depending on
commands used for normal or harsh environments. The first byte is
always the start of message byte. The start of message byte is
either the ASCII “!” character (normal) or the ASCII “#” character
(harsh). The second byte is the address byte. This byte allows
each unit to have a unique address (useful in RS-485 networks).
Since the 232DRIO uses RS-232 communications, this byte is
always the ASCII “0” character and can not be changed. The next
byte is the command character. This byte is ASCII character and

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used to specify which command will be executed by the

X

controller,either the “R” or “S” character. The set output command
requires one argument field (for normal environments) or two
argument fields (data and its complement for harsh environments).
This field contains the fourth and/or fifth data byte.

Command Syntax: ! or # 0 _ _ _
| | | | |
| | | | |
| | | | ~Data Byte
| | | Data Byte
| | Command Byte
| Address Byte
Start of Message Byte

I/O Data Bytes

When constructing commands to manipulate output lines or
when reading the state of the I/O lines it is necessary to know how to
select and interpret the I/O data byte. The three I/O lines are
represented by one data byte.
A byte represents an eight-bit binary number (11111111),
therefore each byte can represent eight I/O lines. Each bit is
assigned a bit position and a weight (value). Refer to Table 3.3.

Table 3.3 – Bit Assignments for I/O Lines

Input → I #
Relay → R #
Bit Position
Hex Weight
Decimal Weight

X X X

X

7 6 5 4 3 2 1 0
80 40 20 10 8 4 2 1
128 64 32 16 8 4 2 1

To set an output to a HIGH state the corresponding bit position
must be set to a "1". Conversely to set an output LOW the
corresponding bit position must be set to a "0". When reading I/O
lines, any bit set to a "0" indicates the corresponding I/O line is in
the LOW state and any bit set to a "1" indicates the corresponding
I/O line is in the HIGH state.

I
#1 R #2 R #1

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Example 3.1 Set Output Lines

Data Byte Relays

Binary

Decimal Hex Relay #2 Relay #1

XXXXXX00 0 0 de-energized de-energized
XXXXXX01 1 1 de-energized energized
XXXXXX10 2 2 energized de-energized
XXXXXX11 3 3 energized energized

Symbol: X don’t cares (default setting should all be “0”)
To energize the relays, the corresponding bit of the data byte must

be set high. Conversely, to de-energize the relays the
corresponding bit of the data byte must be set low.
(00000011, 3 in decimal, 3 in hex: energized both relay #1 and #2)

Example 3.2 Read I/O Lines

Data Byte Returned Status
Binary

Dec Hex ASCII Input #1 Relay #2 Relay #1

00000000 0 00 NUL low de-energ. de-energ.
00000001 1 01 SOH low de-energ. energ.
00000010 2 02 STX low energ. de-energ.
00000011 3 03 ETX low energ. energ.
00000100 4 04 EOT high de-energ. de-energ.
00000101 5 05 ENQ high de-energ. energ.
00000110 6 06 ACK high energ. de-energ.
00000111 7 07 BEL high energ. energ.

Notice that the returned data byte starts at address 00000000 in
binary, 0 in dec., 0 in hex., or NUL in ASCII. From left to right (msb
to lsb), the first five bits are really XXXXX “don’t cares” but are
defaulted as “00000”. The remaining three bits represent input #1,
relay #2, and relay#1, respectively. A “1” or a HIGH represents relay
energized/input present, and a “0” or a LOW represents relay de­energized/input absent.

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Read I/O Lines Command

The Read I/O Lines command returns one data byte (with the “!”)
and two data bytes (data and its complement with the “#”) that
reflects the state of the I/O lines. Bit 2 is Input #1, Bit 1 is Relay #2,
and finally Bit 0 corresponds to Relay #1. If a bit is a "0" then the
state of that I/O line is LOW. If a bit is a "1" then the state of that I/O
line is HIGH.

Command: !0R
Argument: none
Response: the state of input and 2 relays (shown in bold face)
ASCII Example: !0R<NUL>
Dec. Example: !0R<0>
Hex. Example: !0R<0>
Bin. Example: !0R<00000000>
Description: This indicates that the input and both relays are

“0”s or LOW.

Command: #0R
Argument: none
Response: data and its complement, state of the input and 2 relays
(shown in bold face)
ASCII Example: #0R<NUL><blank ‘FF’>
Dec. Example: #0R<0><255>
Hex. Example: #0R<00><FF>
Bin. Example: #0R<00000000><11111111>
Description: This indicates that the input and both relays are “0”s

or LOW. Note that the complement is returned
immediately following the data byte.

Set Output Lines Command

The Set Output Lines command is used to set the states of the
relay outputs. This command requires one data byte (in normal
environment with “!”) or two data bytes (in harsh environment with
“#”), data and its complement. This data byte specifies the output
state of each relay output. Bit 1 is Relay #2, and Bit 0 is Relay #1. If
a bit position is set to a "0" then the state of that output line will be
set LOW. If a bit position is set to a "1" then the state of that output
line will be set HIGH.

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Command: !0S
Argument: {…} (shown in bold face)
Response: none
ASCII Example: !0S<ETX>
Dec. Example: !0S<3>
Hex. Example: !0S<03>
Bin. Example: !0S<00000011>
Description: Relay #2 is energized (“1”), and Relay #1 is

energized (“1”).

Command: #0S
Argument: {…}{~…} (shown in bold face)
Response: none
ASCII Example: #0S<ETX><n>
Dec. Example: #0S<3><252>
Hex. Example: #0S<03><FC>
Bin. Example: #0S<00000011><11111100>
Description: Relay #2 is energized (“1”), and Relay #1 is

energized (“1”). Note that the complement is
returned immediately following the data byte.

NOTE: If any of these lines are defined as inputs the bit settings are
ignored. Since Bit 2 is defined as Input #1 the bit setting is ignored.

Two important ideas to keep in mind when sending commands
back to back or in sequence are the following:

1)If the “!0R” is sent, one character delay must follow immediately
before any other commands are sent.

2)If the “#0R” is sent, two character delay must follow immediately
before any other commands are sent.

For example: 1) “!0R_!0S1”

2) “#0R_ _ #0S1”
Otherwise, the microcontroller will miss the second “!” or “#” and not

interpret the second command at all since it is still trying to transmit
the returned data byte(s) to the user.

Chapter 4 - I/O Interfacing

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This chapter will explain "HIGH" and "LOW" states and show
some general examples of how to interface to the I/O lines. Caution
must be taken not to exceed 232DRIO specifications listed in
Chapter 1 when interfacing to external devices. Failure to stay
within these specifications could result in damage to the unit and will
void warranty.

Figure 4.1 – Board Layout

Opto-isolated Input

As stated earlier, the opto-isolated input line is CMOS/TTL
compatible and can also handle voltages from 0 to +30 Vdc or Vac.
The isolated input is used to sense a HIGH or a LOW state. This
can be accomplished via switch closures, contact closures, or a
solid state digital signal. When this input senses a voltage level
+5Vdc/Vac or above, it will be considered "LOW" and its input state
will be read as a "0" to the PIC® microcontroller. Conversely, when
an input senses a voltage level below +1.50Vdc/Vac, it will be
considered "HIGH" and its input state will be read as a "1" to the PIC
microcontroller. Correspondingly, the PIC will then evaluate the
incoming input and declare it as a “HIGH” if it is a “0” (at least +5V)
and as a “LOW” if it is a “1” (less than +1.5V).

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Figures 4.2 - 4.4 show examples of some typical input interfaces.

232DRIO

Opto Isolated Input

5-30 Vdc/Vac

Figure 4.2 - Switch Input

EXTERNAL CIRCUIT

232DRIO

EXTERNAL CIRCUIT

Opto Isolated Input

5-30 Vdc/Vac

Figure 4.3 - Solid State Input

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232DRIO

EXTERNAL CIRCUIT

Opto Isolated Input

5-30 Vdc/Vac

Figure 4.4 - Isolated Mechanical Input

Relay Outputs

Relay outputs are used to turn external devices on or off. Relay
outputs are CMOS/TTL compatible and can also operate between 0­24Vdc and 0-115Vac. Outputs can be used to control solid state
output modules, CMOS and TTL logic circuits. Caution must be
taken not to exceed the power capability of the outputs. Refer to the
output specifications in Chapter 1.
Setting an output line to a "1" forces the output HIGH, and setting
an output line to a "0" forces the output LOW. Both relays are de-

energized at factory default settings.
NOTE: The relay circuits are not UL® approved for 120 Vac @ 10A

or 30 Vdc @ 8A (resistive) maximum line service in regards to
contact ratings. However, the printed circuit traces were followed
using UL standards (UL #1950) for minimum width and separation.
For the previous reason and safety concerns, we recommend a
maximum continuous rating of 8 amperes. In conclusion, the
voltage should still comply with the rated relay contact voltage of 120
Vac/30 Vdc max. but recommended @ 8A or lower.

It is the customer’s responsibility to determine the ultimate
safety and acceptability of our products. Failure to stay within
these specifications could result in damage to the unit and will
void warranty.

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Figures 4.5 - 4.6 show examples of some typical output interfaces.

+12 Vdc

232DRIO

+12 Vdc

N/C

EXTERNAL CIRCUIT

+5 Vdc

0-30 Vdc @ 8A max.
0-120 Vac @ 10A max.

N/O

1K

Common

Figure 4.5 – Isolated Connection to External Circuit

232DRIO

EXTERNAL CIRCUIT

N/C

N/O

Common

Common

0-30 Vdc @ 8A max.

0-120 Vac @ 10A max.

Figure 4.6 – Isolated Connection to External Devices

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Chapter 5 - Software

This chapter will be divided into two sections. The first section
covers programming techniques for opening/closing a com port,
receiving data, and manipulating data in QuickBasic and C/C++.
The second section discusses how to install and run the
demonstration program on an IBM PC or compatible.

Table 5.1 - Digital I/O Mask Values

Mask Values

I/O Line # Hexadecimal Decimal

Relay #1 1H (0x01) 1
Relay #2 2H (0x02) 2
Input #1 4H (0x04) 4
X 8H (0x08) 8
X 10H (0x10) 16

X 20H (0x20) 32
X 40H (0x40) 64
X 80H (0x80) 128

Symbol: X Don’t cares (default setting should all be “0”)

Programming Techniques

232DRIO.LIB

Opening a COM Port

HComDev = initComPort(unsigned short addr, unsigned
char irq, unsigned long baud, unsigned short PortIndex)

The last parameter, PortIndex will always be 0 for programming the
232DRIO module:

InitComPort() Æ Returns 0 on error
For example, the code to open COM port 1 and setting the baud rate
to 9600 would be:
HComDev = initComPort(0x03F8,4,9600,0)

Closing a COM Port
DeinitComPort(hComDev) Æ No return value

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QuickBasic (DEMO232.EXE and DEMO232.BAS)

This section shows steps and examples of programming the
232DRIO in QuickBasic. If you are programming in another
language, this section can be helpful as a guideline for programming
the 232DRIO.

Using the 232DRIO.LIB with QuickBasic:

Using this library will make it easier to program the 232DRIO
module and allows greater flexibility in choosing serial ports. At the
DOS prompt, start QuickBasic with the 232DRIO Quick Library by
typing:
QB program.bas /L 232DRIO.QLB
This allows you to call the 232DRIO functions from the QuickBasic
editor.
‘$INCLUDE: ‘232DRIO.BI’ Æ Include the function definitions
mem = SETMEM(-2000) Æ Tell QB to set aside memory for the
232DRIO library to use

Read I/O States Command

states = bbDRIOReadIOLines(hComDev, mode)

When the line is executed, states will contain a byte that can be
read by “ANDing” states with the appropriate mask.

Example 5.1 - Determining the status of Relay #1
If (states AND 0x01) Æ True if relay 1 is on
If (states & 0x01)

Set Output States Command

status = bbDRIOSetOutputLines(unsigned short hComDev,

unsigned char states, int mode) Æ Returns a negative number

on error

Example 5.2 – Various ways to energized/de-energized Relay #1

1) A relay can be energized by “ORing” states with the

appropriate mask.
states = states OR &H01 Æ Will energized Relay #1

2) A relay can be de-energized by “ANDing” with the

complement of the mask. (~mask)
states = states AND &HFE Æ Will de-energized Relay #1

3) A relay can be switched by “Exclusive ORing” states with the

appropriate mask.

states = states XOR &H01 Æ Will energized Relay #1 if it is

de-energized or vice versa

20 232DRIO-0308 Manual

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C/C++ (DEMO232.EXE and DEMO232.CPP)

DEMO232.CPP is a demonstration program for use with B&B
Electronics model 232DRIO module. Much of the work associated
with using COM ports in C/C++ has been made easier by including
the 232DRIO.LIB with this program.
Including “232DRIO.H” in the pre-processor directive and
compiling your .cpp file as a project along with the 232DRIO.LIB file
will enable you to use the following functions in your program.

Important Note: For Borland C++, the compiler must be set
for large memory model for your program to compile properly.
Access this by the pulldown menu Options/Compiler/Code
Generation/ to change model size and click on ok.

#include”232DRIO.H”

void main ()
{
/* put your program here */
}

Read I/O States Command

states = bbDRIO_ReadIOLines(hComDev, int mode)
Mode is 1 if harsh environment is enabled or 0 if disabled. Returns

–1 if an error occurred.

Example 5.3 – Determining the status of Relay #1
If(states & 0x01) Æ True if Relay #1 is on

When the line is executed, states will contain a byte that can by

read by “ANDing” states with the appropriate mask.

Set Output States Command

bbDRIO_SetOutputLines(unsigned short hComDev,

unsigned char states, int mode)

Example 5.4 – Various ways to energized/de-energized Relay #1

1) A relay can be energized by “ORing” states with the

appropriate mask.
states |= 0x01 Æ Will energized Relay #1

2) A relay can be de-energized by “ANDing” with the
complement of the mask. (~mask)

states &= 0xFE Æ Will de-energized Relay #1

3) A relay can be switched by “Exclusive ORing” states with the
appropriate mask.

states ^= 0x01 Æ Will energized Relay #1 if it is de-

energized or vice versa

232DRIO-0308 Manual 21

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Demonstration Program

The Demonstration Programs (IBM PC or Compatible) provide
the user with examples of how to receive and transmit commands to
the 232DRIO. The DEMO232.EXE is the executable program and
the DEMO232.BAS file is the source code in QuickBasic. The
DEMO232.EXE is the executable program and the DEMO232.CPP
file is the source code in C/C++. The source codes provide an
illustration of how to send and receive commands from the
232DRIO.

NOTE: This is a demonstration program only and not intended for
system applications.

Running Demonstration Program

Before you can run the demonstration program you must run the
install program in the Hard Drive Installation section. If you are
running Windows, exit Windows to DOS.

To run the program follow these steps from the DOS prompt:

QuickBasic

1. Type CD \BASIC and press the <ENTER> key.

2. Type DEMO232 and press the <ENTER> key.

C/C++

1. Type CD \BC and press the <ENTER> key.

2. Type DEMO232 and press the <ENTER> key.

22 232DRIO-0308 Manual

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APPENDIX A

ASCII Character Codes

232DRIO-0308 Manual Appendix A A-1

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DECIMAL to HEX to ASCII CONVERSION TABLE

DEC HEX ASCII KEY DEC HEX ASCII DEC HEX ASCII DEC HEX ASCII

0 0 NUL ctrl @ 32 20 SP 64 40 @ 96 60 `
1 1 SOH ctrl A 33 21 ! 65 41 A 97 61 a
2 2 STX ctrl B 34 22 “ 66 42 B 98 62 b
3 3 ETX ctrl C 35 23 # 67 43 C 99 63 c
4 4 EOT ctrl D 36 24 $ 68 44 D 100 64 d
5 5 ENQ ctrl E 37 25 % 69 45 E 101 65 e
6 6 ACK ctrl F 38 26 & 70 46 F 102 66 f
7 7 BEL ctrl G 39 27 ' 71 47 G 103 67 g
8 8 BS ctrl H 40 28 ( 72 48 H 104 68 h

9 9 HT ctrl I 41 29 ) 73 49 I 105 69 i
10 A LF ctrl J 42 2A * 74 4A J 106 6A j
11 B VT ctrl K 43 2B + 75 4B K 107 6B k
12 C FF ctrl L 44 2C , 76 4C L 108 6C l
13 D CR ctrl M 45 2D - 77 4D M 109 6D m
14 E SO ctrl N 46 2E . 78 4E N 110 6E n
15 F SI ctrl O 47 2F / 79 4F O 111 6F o
16 10 DLE ctrl P 48 30 0 80 50 P 112 70 p
17 11 DC1 ctrl Q 49 31 1 81 51 Q 113 71 q
18 12 DC2 ctrl R 50 32 2 82 52 R 114 72 r
19 13 DC3 ctrl S 51 33 3 83 53 S 115 73 s
20 14 DC4 ctrl T 52 34 4 84 54 T 116 74 t
21 15 NAK ctrl U 53 35 5 85 55 U 117 75 u
22 16 SYN ctrl V 54 36 6 86 56 V 118 76 v
23 17 ETB ctrl W 55 37 7 87 57 W 119 77 w
24 18 CAN ctrl X 56 38 8 88 58 X 120 78 x
25 19 EM ctrl Y 57 39 9 89 59 Y 121 79 y
26 1A SUB ctrl Z 58 3A : 90 5A Z 122 7A z
27 1B ESC ctrl [ 59 3B ; 91 5B [ 123 7B {
28 1C FS ctrl \ 60 3C < 92 5C \ 124 7C |
29 1D GS ctrl ] 61 3D = 93 5D ] 125 7D }
30 1E RS ctrl ^ 62 3E > 94 5E ^ 126 7E ~
31 1F US ctrl _ 63 3F ? 95 5F _ 127 7F DEL

A-2 Appendix A 232DRIO-0308 Manual

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APPENDIX B

Hexadecimal/Decimal Conversions

The decimal (base 10) numbering system represents each

position in successive powers of 10, with each decimal symbol

having a value from 0 to 9. The hexadecimal (base 16) numbering

system represents each position in successive powers of 16 with

each hex symbol having a value of 0 to 15. Since each hex position

must have a single symbol, the symbols "A" through "F" are

assigned to values 10 through 15 respectively. Refer to Table 1.

The information and examples to follow will explain how to convert

from a decimal number to a hexadecimal number and vice versa.

Table 1.

Decimal

Value

0 0
1 1
2 2
3 3
4 4
5 5
6 6
7 7
8 8

9 9
10 A
11 B
12 C
13 D
14 E
15 F

Hexadecimal

Symbol

232DRIO-0308 Manual Appendix B B-1

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Hexadecimal to Decimal Conversion:
Decimal = (1st Hex digit x 4096) +

(2nd Hex digit x 256) +
(3rd Hex digit x 16) +

(4th Hex digit)
Each "Hex digit" is the decimal equivalent value of the
hexadecimal symbol.

Example: Convert 10FC hexadecimal to decimal.

1 x 4096 = 4096

0 x 256 = 0
15 x 16 = 240
12 x 1 = 12

4348

10FC hex equals 4348 decimal.

Decimal to Hexadecimal Conversion:

Example: Convert 4348 decimal to hexadecimal.

4096 4348 = 1 = 1 (1st Hex digit)

4096

256 252 = 0 = 0 (2nd Hex digit)

0

16 252 = 15 = F (3rd Hex digit)

240

1 12 = 12 = C (4th Hex digit)

12
0

4348 decimal equals 10FC hexadecimal.

B-2 Appendix B 232DRIO-0308 Manual

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