should there be one or two rs232 while interfacing gsm module with 8051

we are having a problem while interfacing a gsm module with 8051, we are able to correctly interface gsm module and 8051 with pc seperately.but while both are connected together we are not able to sent...
should there be one or two rs232 while interfacing gsm module with 8051

we are having a problem while interfacing a gsm module with 8051, we are able to correctly interface gsm module and 8051 with pc seperately.but while both are connected together we are not able to sent...
Interfacing of GSM module with 8051

hello sir/madam, This forum is very good. last time also i had used this.Got very nice information.:) Now i want to interface GSM module with 8051. 1)can i do it without using hyper terminal? ...
Interfacing of GSM module with 8051

hello sir/madam, This forum is very good. last time also i had used this.Got very nice information.:) Now i want to interface GSM module with 8051. 1)can i do it without using hyper terminal? ...
Cant interface 8051 with a GSM module

i cant interface NXP2148 with the GSM module. i have used the UART1 (through RS232 DB9 using RXD, TXD and ground) to interface with the GSM module at 9600. when i send the command AT<CR> through hyperterminal...