RS232 communication

[ivan_ult]

Hi everyone, I've done a simple circuit and program for communicate 3 serial devices (successfully) I've tested with 3 terminal connections sessions and works, however I can't communicate this circuit with a specific machine (I don't know if you guy are familiarized with UIC Radials Inserters Machines, actually 14 years old).

My doubt is that when I communicate with hyperterminal, if I type a character in one of the ports the PIC writes to the other 2, and in the hyperterminal window I don't see the character in the sender window just in the receptors, so when I connect my PC directly with this machine (radial) I can see the characters I'm writing, in fact the machine session show me a prompt.

I don't know if those are different types of communication and its necessary to do something different.

Part of the code: