[PIC] i am trying to operate air conditioner with pic 18f4550 and sim900 help!

[Kfir Maymon]

hi,
i am trying to operate air conditioner with pic 18f4550 and sim900,
every thing work great when i sending command throw pc terminal and sometime it`s work even with the pic.

i think my problem is with the timing.


hear is the code:
View attachment 18f4550 sim900 uart.rar

 

[milan.rajik]

What is the actual problem ? What Compiler are you using ?

In your code I don't see any code piece which operates the relay controlling the AC. Do you just want to turn ON/OFF AC using SIM900 and a microcontroller ?

 

[Kfir Maymon]

sorry,
i am using mikroc a IR led to control the air conditioner and its working,
my problem is when the pic communicate with sim900.
i try to explain with this line:

pic send:AT+CMGF=1
sim900 send:OK
pic send:AT+CMGDA="DEL ALL"
sim900 send:OK
"when sim get sms"
sim900 send:\r\n +CMTI: "SM",1 \r\n
pic send:AT+CMGL="ALL"
sim900 send: \r\n +CMGL: 1,"REC UNREAD","+972542230352","","14/09/23,21:11:21+12" \r\n
ACON(sms content)\r\n

OK

after sim900 send "\r\n +CMTI: "SM",1 \r\n"

nothing happen, if i`m using a pc terminal to send commands to pic (instead the sim900)
everything work fine

 

[milan.rajik]

You have to issue "AT+CMGR=1\r\n" to read the message at index 1. You have to parse the SMS and make decisions based upon data in SMS.

 

[Kfir Maymon]

this command AT+CMGL="ALL
read all massage

 

[milan.rajik]

For your method AT+CMGL=ALL is ok because you are deleting all messages initially and so the index will be pointing to 1 but it is good to use AT+CMGR=x and read only the required SMS.

 

[Kfir Maymon]

thanks, i delete all just to be sure