Internet PLC Forum

 
1) What software are you using to send the "ASCII" command?  

---> I use Sample Programm(visual basic) downloaded from Frequently Asked Questions. And COM port is correct. While a T100MD PLC is not running, a host computer can read . While a T100MD PLC is  running, a host computer can't read using VBasic comms.
 
  Are you able to perform online monitoring and program transfer using TRiLOGI software?  

--->While a T100MD PLC is  running, I can't monitoring using TRiLOGI software  

I hope append ladder source I was made.
I think that ladder source aroused troubles in communication.