Table of Contents
ii
Example using RS-485 Mode .......................................... 22
7. Operation .................................................................. 23
Configuring Handshaking and Receive-Only Modes ........................ 23
Using RTS/CTS and Automatic Handshaking ........................... 23
RS-485 Half-Duplex Mode ........................................................ 23
Using the RS-232 Link in Receive-Only Mode ......................... 24
Power Conservation .......................................................................... 24
8. Troubleshooting and Maintenance ......................... 25
Troubleshooting ................................................................................ 25
Upgrading the Operating System ............................................... 27
Operating System Signature Errors ............................................ 27
Checking the Operating System Version and Signature ............ 28
Appendices
A. Using the Handshaking Lines for General
Input/Output ......................................................... A-1
The Input Pin (CTS/Pin 11) ............................................................. A-1
The Output Pin (RTS/Pin 8) ............................................................ A-2
B. Matching SDM-SIO1A Connections to an
SDM-SIO1 ............................................................. B-1
Figures
1-1. SDM-SIO1A Serial Input/Output Module .......................................... 1
7-1. RS-485 Internal Circuit Diagram ...................................................... 25
Tables
6-1. SDM Address Settings ........................................................................ 9
6-2. SDM-SIO1A Terminal Labels and Functions ................................... 10
6-3. SDM-SIO1A Functional Description of the Connections ................. 10
6-4. Communications Port Parameters RS-232 ........................................ 17
6-5. Communications Port Parameters RS-485 Full Duplex .................... 17
6-6. Communications Port Parameters RS-485 Half Duplex ................... 18
6-7. Communications Port Parameters RS-232 Receive-Only Mode ....... 18
B-1. Pin Cross Connection Table for SDM-SIO1 to SDM-SIO1A ......... B-1
CRBasic Examples
6-1. RS-232 Mode Example ..................................................................... 21
6-2. RS-485 Mode Example ..................................................................... 22
8-1. Checking the Operating System Version and Signature .................... 28
A-1. Detecting the State of the Input Line ............................................... A-1