I follow the instructions to testing sim900A, but ONLY can receive message/call from another cellphones, NOT call/send from sim900 to any cellphones. Anybody have experiences on this case?
I cannot even sent AT command to test operation status; receive message is okay now; here my logfile. Thank you in advance.
NORMAL POWER DOWN
ÿÿÿÿ
RDY
+CFUN: 1
+CPIN: READY
Call Ready
+CMT: "+8498???????","Xi l","14/09/28,22:50:44+28"
Trying...
AT
Dannable: I just connected sim900A and PC and using Terminal software to send AT command, not develop any code yet.
And, I found that I cannot send string "CR" character by Terminal; I make a test by convert to Hexa, sending "AT\n" by "41-54-D" instead, It can respond OK now.
So, do you know how can I send CR+LF after each commands, in case no need convert?