SMS control for Relays

[charudatt]

Hello all,

I successfully tried out this code to control a bank of eight relays using SMS over GSM network. Just thought of sharing it with all so that others could use it.

Hardware setup:
Processor : 16F72
PortB : Connected to relays via ULN2803 driver IC.
PortA: 16x2 LCD
Modem : SIMCOM GSM/GPRS Tri Modem

Consideration : The Modem is configured @ 9600 baud. Pin #7 and #8 are shorted at the 9 pin D connector on the Modem Side. AT+CMGF=Text. ATE0 (no echo). The code shows control of only 4 relays but you can add all eight to it. This code can be optimised for code space , but can be used as a starting point.

regards