Problem on UART handshaking signals


#1

Hi all,

I am working Q24 Classics, in the UART connection, i am getting a clear response at Null Modem connection while connecting only TxD and RxD.

But in case of Hardware connection, while utilising all the 9 pins, i am not getting reponse from handshaking signals.
Especially when DTR, RTS is asserted to 0, we are not getting 0 logic level at the DSR and CTS pins.
Instead of that when i send my data, i receiving the data at RxD, CTS and DSR pins.
Because of these problem’s, i am not receiving any response for AT commands.

Also i am sure that the RS232 miscellaneous connections are good, i suspect on the H/W or S/W settings with wireless CPU and OpenAT.

Kindly help me