communicate with PLC fx_1n via rs422 (programming port) need some help !

[draco]

im trying to connect a fx-1n PLC with hyperterminal using USB-SC09 (rs-232<->rs-422 adaptor). im using computer link with a dedicated protocol (loop back mode). this is my plc program
M8002
---||-------[mov H0 D8121]
|-----[mov K0 D8129]
|-----[mov H6080 D8120]
-----------[end]
so i connect USB cable to PLC and program it. after that i turn the power off and turn on. On hyperterminal i config Br 9600,data bits=7,parity none, stop bit=1 and send a string:
"\ENQ00FFTT204ABCD34[/B]".
I expected to get the loopback data but i just get "\NAK\NAK\NAK\NAK.." maybe 14 NAK without error code. I m give it up today and i need some help from you, guys! pls.
Ps: thanks to every comment.

 

[electrodynatronic]

You could try trouble shooting your hardware with an actual loopback. I'd use Bray Terminal too instead of Hyperterminal I like Bray Terminal much better.

 

[draco]

thanks but this is the loopback command so if the PLC cannot respond this may be the PLC is broken. is it right? i have already test the run and stop command by FX-WIN-E software and it worked