Sending command throw HyperTerminal and COMM control: what difference?

[Ech Zi]

I try to write application for Siemens modem.
If I send messages to modem throu HyperTerminal, I receive OK or Error in accordance. But If I send message simplu throw COMM control- I receive copy of all messages iSend and sometimes ERROR message.
What mast I add to message content in character flow?

[anjana29]

Hi Zi,

I am also faciing the similar problem as yours. Please let me know how did you solve this problem.

Thanks in advance,
Anjana