[SOLVED] How to send at commands to uart of pic32

horace1 said:

connect the SIM900 to PIC32 UARTs plus a UART for PC communications

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Dhruv@aks said:

I am using the uart2rx and tx to connect to the pic32 but how do i connect this to the sim900 device.I am looking for the cicuit diagram for it or the connecting pin.
i can connect them seprately.But how do i send commands to the sim900 using pic32.

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   UART1Init(115200);            
   UART2Init(115200);
   while(1)
           {
           if(UART2CharReady()) UART1PutChar(UART2GetChar());
           if(UART1CharReady()) UART2PutChar(UART1GetChar());
           }

horace1 said:

which PIC32 are u using?
for eaxmple connect the PC to UART2 and the modem to UART1
I have a PIC32MX575F512H PC Rx to pin 31 and Tx to pin 32 with modem (a WISMO228) Rx pin 51 and Tx pin 52
many of the moden PIC32s have Programmable Pin Select with means you can select the Tx and Rx pins at run tim (also makes PCB layout simpler)

simple code for the PC to communicate with the modem looks like

Code:

   UART1Init(115200);            
   UART2Init(115200);
   while(1)
           {
           if(UART2CharReady()) UART1PutChar(UART2GetChar());
           if(UART1CharReady()) UART2PutChar(UART1GetChar());
           }

it is a good idea to interrupt control the UART receivers with data into ring buffers or you mau loose data (in particular if the PC baudrate is less then the modem

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