AIX

I have software running under AIX 5.3 that should communicate with a special device using standard communication protocol (Modbus) using serial RS-232 line

The settings are correct in both sides, But I can't establish a connection.
I suspect that there's something that I should do regarding the tty0 ...

(screen shot of tty0 are attached)

I appreciate any input ..

Thanks in advance

Because the IBM web site is rubbish I cannot find if you adapter is an onboard serial port, or a PCI adapter serial card.
The onboard serial ports are limited and do not comply with the RS232 standards.
If you need to use anything other than a terminal, and it seems you do need a little bit beyond simple serial console connection, then you'll need to buy a PCI RS232 adapter and use that, if you are not already.
HTH

Thanks dukessd for your reply,

I had found the solution (from the software vendor support).

They said that some pins in the serial port (on the PCI card) should be connected together or else the process using this port will hang !!

These pins are:
7 to 8
1 to 4 to 9

Also, this link may help anybody else regarding this issue.

Thanks for posting back ayman metwally.