Can it be the case that the modem is configured for echoing the received characters?
Check your variable rxd_cnt, it might overflow / underflow.
thats very true. would check it out now.
I needed to connect the battery to the contact VBTA for SIM900
Otherwise - after the first activation of the transmitter modem stops responding.
Maybe you will be interested in the project for SIM900
M590E has a lot in common with it
PSoC4: GSM Modem
Thanks a lot. was really helpful...
the echo was actually the fault. thanks alot. is it possible to ready only the message section of a CMGR or CMGL AT command????