And another part (not the last one) of my UART series.
Here is a piece of code for the PC to establish a connection to the RS232 testboard and to communicate with it..
It is just an example how to interface with the board and not a complete library. The example application sets the outputs, reads in the inputs, reads the analog input and calculates the voltage on that pin. Everything with hardware handshake.
But you need the right cable for the handshake. Otherwise change the "true" in the uartSend commands to "false" and delete the handshake activation.
The software is tested under DOS with TurboC and under Ubuntu Linux with GCC. The source compiles with Open Watcom too - but the Watcom binary is not tested under DOS yet.
I changed the compiler preprocessor macros for the recognition of operating systems and compilers several times - but did not test every combination with every operatin system and every compiler. Perhaps you need to figure out the correct setup for your system (or just delete the stuff you do not need).
It took me several hours to figure out, that linux needs an activated FIFO control register. Otherwise the data transmission will fail in 99% of the cases.