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CPU Board Connections
The are three types of external connections on the CPU board, the configuration serial
port connector, the general purpose I/O connector and the in-circuit programming
connectors.
Basic Checklist
Make sure you connect the CPU’s DB-9 connector to your PC so you can use the
CONFIG program to configure your control system.
CPU Board Serial Port Connector
This connection is a standard RS-232 ASCII interface between the control system and
your computer. It is used to configure the control system under computer control.
Connector pin outs…
Pin 2 - Rx data in
Pin 3 - Tx data out
Pin 5 - Ground
The configuration serial port is the male DB-9 connector on the front edge of the board.
This connection is not used in normal operation. When using the optional PC-based
configuration software, the PCs serial port is plugged in this connector.
PC Configuration Cable
This cable connects your computer to the main CPU board for upload and downloading
the control systems configuration. The programming cable is a straight through cable.
Connections required are pin 2 to 2, 3 to 3 and 5 to 5. The crossover of txd / rxd is done
on the CPU board. Note that most female to female cable available in computer stores
swap pins 2 and 3, so you may need to make your own cable.