CCS/TMS320F28030: Sending ascci data corruption when while loop is removed

Allen12

Part Number: TMS320F28030

Tool/software: Code Composer Studio

Hello, data is transmitted via RS232 Bit bang, using the while loop there are no issues, the data s transmitted correctly with or without the debugger.

When the while loop is commented out the data is garbage (fail), with and without the debuggert

#define UART_WAIT_ONE_BIT for (delay1 = 1; delay1 <43; delay1++) {asm(" NOP"); asm(" NOP"); asm(" NOP");asm(" NOP"); asm(" NOP"); asm(" NOP"); asm(" NOP"); asm(" NOP"); asm(" NOP"); asm(" NOP");}

Uint8 FwRevision[] = {"12345678- A"};

PASS:

while(1){

tx_FirmwareSerialNumber(FwRevision);

}

FAIL:

//while(1){

tx_FirmwareSerialNumber(FwRevision);

//}

Sub

void tx_FirmwareSerialNumber(Uint8 *ptrFwRevision

Uint8 delay1,byteCount,mask,bitIndex;

byteCount = 11;

mask = 0x01;

byteCount = 0;

for(byteCount = 0; byteCount < 11; byteCount++){

//Send start Bit

GpioDataRegs.GPACLEAR.bit.GPIO23 = 1;

UART_WAIT_ONE_BIT

//Transmit 8 bits, shift the data

for(bitIndex = 0; bitIndex <8; bitIndex++){

if(ptrFwRevision[byteCount] & mask){

GpioDataRegs.GPASET.bit.GPIO23 = 1;

}

else

{

GpioDataRegs.GPACLEAR.bit.GPIO23 = 1;

}

//LSB First,

mask <<= 1;

UART_WAIT_ONE_BIT

}

//Tx Stop bit

GpioDataRegs.GPASET.bit.GPIO23 = 1;

UART_WAIT_ONE_BIT

mask = 0x01;

}//End while

over 4 years ago

0 Whitney Dewey over 4 years ago

TI__Guru 50575 points

Nothing is jumping out at me just from looking at the code. I have a few questions that may help narrow it down.

Is the manner in which the data gets corrupted consistent or does it vary from run to run?
Do you have optimization turned on and if so does it make a difference to turn it off?
Do you have any means of looking at the signals (logic analyzer or similar) to see if they look okay?

Thanks,

Whitney

0 Allen12 over 4 years ago in reply to Whitney Dewey

Intellectual 425 points

1.No

2, off

3. without the delay this section runs faster

0 Allen12 over 4 years ago in reply to Allen12

Intellectual 425 points

3. oscilloscope, failed 40us Vs ~1ms, could this be the optimizer

the code which uses Timer is unaffected

0 Whitney Dewey over 3 years ago in reply to Allen12

TI__Guru 50575 points

Since you have optimization turned off, that shouldn't be the issue. Thanks for confirming.

I don't understand what you mean in your answer to 3. "oscilloscope, failed 40us Vs ~1ms"? What delay is changing--UART_WAIT_ONE_BIT? How frequently you are calling the function in question?

Whitney

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CCS/TMS320F28030: Sending ascci data corruption when while loop is removed