Did you check that RDA interrupt worked correctly and chk_gprs=1 when you sent the desired string? Maybe use LED toggle.
Did you check that TIMER1 periodic interrupt worked correctly?
And you sho ...
Dear sir.
I used PIC18F4553 and PIC16F877 with CCS V4.
I did multi-file compilation unit for my project and it worked fine.
But when I used dynamic memory functions (calloc/malloc) in my program ...