couldn't send data from TMS320f28335 to PC

Fikadu Degefa95

Other Parts Discussed in Thread: TMS320F28335, MAX232

Hello Every One,

While receiving data from PC, my program works perfectly. But while sending data from TMS320F28335 to PC, it couldn't reach to.The data could be written to the Tx Register(ScibRegs.SCITXBUF) that could be seen on watch window. I have also checked the Tx line through oscilloscope. Nothing appears. What could be a problem?

Thank you in advance for your help.

over 9 years ago

0 David M. Alter over 9 years ago

TI__Guru 61235 points

Fikadu,

Check the pin multiplexing for the TX pin. Do you have it set correctly for SCI TX function?

- David

0 Fikadu Degefa95 over 9 years ago in reply to David M. Alter

Intellectual 350 points

Dear David, Thank you

As to my understanding , the pin configuration looks okay. Here bellow:

void InitScibGpio()
{
EALLOW;

GpioCtrlRegs.GPAPUD.bit.GPIO14 = 0; // Enable pull-up for GPIO14 (SCITXDB)
GpioCtrlRegs.GPAPUD.bit.GPIO15 = 0; // Enable pull-up for GPIO15 (SCIRXDB)

GpioCtrlRegs.GPAQSEL1.bit.GPIO15 = 3; // Asynch input GPIO15 (SCIRXDB)

GpioCtrlRegs.GPAMUX1.bit.GPIO14 = 2; // Configure GPIO14 for SCITXDB operation
GpioCtrlRegs.GPAMUX1.bit.GPIO15 = 2; // Configure GPIO15 for SCIRXDB operation

EDIS;
}

0 David M. Alter over 9 years ago in reply to Fikadu Degefa95

TI__Guru 61235 points

Fikadu,

Is this your own board or a EVM? Sometimes on an EVM the SCI TX is routed through a jumper. Are you checking the TX data with the scope at the pin, or further downstream on the board?

I assume you have SCICTL1.TXENA set to 1 to enable transmit?

- David

0 Fikadu Degefa95 over 9 years ago in reply to David M. Alter

Intellectual 350 points

David,

it is my own board. Because it too tight to check at a pin, I couldn't check data flow. But, I checked after max232 and there is no signal on Tx line.

SCICTL1.TXENA is already set to 1 to enable Tx.

Thank you once again.

0 David M. Alter over 9 years ago in reply to Fikadu Degefa95

TI__Guru 61235 points

Fikadu,

Are you able to check the TX pin BEFORE the max232 chip?

Also, you can try configuring the pin as GPIO and twiddle it up and down, and see if the TX line responds. If not, it could indicate a damaged device.

- David

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couldn't send data from TMS320f28335 to PC