Hi All

I am doing a project recently requires RS232 communication between a
hpux workstation and a robot. This machine has its own RS232
communication protocol which can accept commands and return result
from queries. The RS232 connection requirement is very simple.

the workstation the machine
9 pins connector 25 pins connector

Pin 2(Rx) connected to Pin 2(Tx)
Pin 3(Tx) connected to Pin 3(Rx)
Pin 5(Gnd) connected to Pin 7(Gnd)

Ive wrote a C code to control the machine. Apparently, the machine is
accepting the commands from the C program and performed its tasks, but
wouldnt response to the queries that Ive sent from the program.
Therefore Ive probe(pin2 - Tx) from the 25 pins Dsub connector and
found that the machine is actually returning the expected result but
the serial port is not set to read the result. The read result return
-1.

I am not a RS232 programmer and this is the first time I am doing so.
But I think it must something to do with the RS232 options that I
should set in my hpux box.
All kinds of RS232 related helps are appreciated. Thanks in advance.
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