TMS320F2800137: serial Communication

manoj kumar

Part Number: TMS320F2800137
Other Parts Discussed in Thread: SYSCONFIG

while doing Sci communication, data is not coming to RX buff SAR bits, i have configure SCIA like this

SciaRegs.SCICTL1.bit.TXWAKE=1;
SciaRegs.SCIHBAUD.bit.BAUD=0x05;
SciaRegs.SCILBAUD.bit.BAUD=0x15;
SciaRegs.SCICCR.bit.SCICHAR=7;
// SciaRegs.SCICCR.bit.ADDRIDLE_MODE=1;
SciaRegs.SCICCR.bit.PARITYENA=1;
SciaRegs.SCICCR.bit.PARITY=1;
SciaRegs.SCICCR.bit.STOPBITS=1;
SciaRegs.SCIRXST.bit.RXWAKE =1;
SciaRegs.SCICTL1.bit.TXENA=1;
SciaRegs.SCICTL1.bit.RXENA=1;
SciaRegs.SCICTL1.bit.SWRESET=1;
SciaRegs.SCICTL2.bit.RXBKINTENA=1;
//SciaRegs.SCIFFRX.all = 0x0022;
SciaRegs.SCIFFRX.bit.RXFFIENA=1;
SciaRegs.SCIFFRX.bit.RXFIFORESET = 1;
SciaRegs.SCICTL1.all = 0x0023;

in isr

{

RecData= SciaRegs.SCIRXBUF.bit.SAR;

//////to clear flags////////////////
//SciaRegs.SCICTL1.bit.SWRESET=1;
SciaRegs.SCIFFRX.bit.RXFFOVRCLR=1;
SciaRegs.SCIFFRX.bit.RXFFINTCLR=1;
// PieCtrlRegs.PIEACK.bit.ACK8=;
SciaRegs.SCIFFRX.bit.RXFIFORESET = 1;
PieCtrlRegs.PIEACK.all = PIEACK_GROUP9;

}

over 2 years ago

0 manoj kumar over 2 years ago

Prodigy 110 points

when i enable loopback it is working fine but when i short tx and rx pins its not working. its urgent.

0 Vince over 2 years ago in reply to manoj kumar

TI__Mastermind 19795 points

Hi Manoj,

Have you configured the correct GPIOs to be muxed as SCI TX and SCI RX? By default, SCI does not go out to the pin.

Please use Sysconfig to see how to do this (Sysconfig generates all the required code for SCI).

Regards,

Vince

0 manoj kumar over 2 years ago in reply to Vince

Prodigy 110 points

sysconfig is not giving me the acesess to all registers and it has some bugs.

gpio config is as below

///Gpio28/////
GpioCtrlRegs.GPAQSEL2.bit.GPIO28=2;
GpioCtrlRegs.GPAGMUX2.bit.GPIO28=0;
GpioCtrlRegs.GPAMUX2.bit.GPIO28=1; // configure as SCIA RX
GpioCtrlRegs.GPAPUD.bit.GPIO28=0; //pullup enabled
///Gpio29////
GpioCtrlRegs.GPAGMUX2.bit.GPIO29=0;
GpioCtrlRegs.GPAMUX2.bit.GPIO29=1; // configure as SCIA TX
GpioCtrlRegs.GPAPUD.bit.GPIO29=0; //pullup enabled

interrupt

PieCtrlRegs.PIEIER9.bit.INTx1=1; //SCIARX interrupt

IER |= M_INT9;

PieVectTable.SCIA_RX_INT= &SciARxIsr; // Function for SCIC interrupt

when i enable loopback data transfer is happening. please help me with this.

0 Vince over 2 years ago in reply to manoj kumar

TI__Mastermind 19795 points

Hi Manoj,

Can you provide a scope capture of TX and RX pins? I believe there is still something wrong where SCI is not reaching the pins you are looking to output to.

That is the only way it would work correctly in loopback but not with pins shorted.

Also double check the pins your are using are the right pins.

https://e2e.ti.com/support/microcontrollers/c2000-microcontrollers-group/c2000/f/c2000-microcontrollers-forum/1031947/faq-my-c2000-sci-is-not-transmitting-and-or-receiving-data-correctly-how-do-i-fix-this

Regards,

Vince

0 manoj kumar over 2 years ago in reply to Vince

Prodigy 110 points

waveform is signal on TX pin, hardware is launchpad IO28 and IO29 switch is selected to Booster pack

0 Vince over 2 years ago in reply to manoj kumar

TI__Mastermind 19795 points

Manoj,

Those two pins (IO28/29) are being used by hardware already as shown in the image below in Sysconfig:

You have to change your jumpers on the launchpad to make the TX and RX go out to the pin.

Please scope capture the RX pin and see if the signal is reaching that pin.

Regards,

Vince

0 manoj kumar over 2 years ago in reply to Vince

Prodigy 110 points

in the above image ch1 signal is the signal on Tx pin, that means signals are coming to boosterpack, i kept the SEL1 switch to 1 which makes the signals route to booster pack.

0 Vince over 2 years ago in reply to manoj kumar

TI__Mastermind 19795 points

Hi Manoj,

Can you scope capture the RX pin? Looks like the signal is probably not reaching the RX pin. And even then, it looks like nothing is connected between IO28 and IO29, so you need to jumper those pins with a wire.

Regards,

Vince

0 manoj kumar over 2 years ago in reply to Vince

Prodigy 110 points

i kept that photo for a reference saying the SEL1 switch is kept to booster pack. i shorted the IO28 and IO29 with jumper(in this photo it is not there).

0 Vince over 2 years ago in reply to manoj kumar

TI__Mastermind 19795 points

Hi Manoj,

Can you please try once with Sysconfig and use it at least as reference for what must be generated?

manoj kumar said:
sysconfig is not giving me the acesess to all registers and it has some bugs.

Please provide what registers you are trying to access that sysconfig does not allow, and what bugs you are referring to.

Regards,

Vince

0 manoj kumar over 2 years ago in reply to Vince

Prodigy 110 points

i understood sysconfig makes the work easy, but we developed all the code with bit field, only sci communication i have problem and please simulate with the configurations i use and confirm me that what ever i did id correct.

0 Vince over 2 years ago in reply to manoj kumar

TI__Mastermind 19795 points

Hi manoj,

Are you using device.h and have you set the "_LAUNCHXL_F2800137" pre-defined symbol?

See the highlighted text in the board user's guide:

As for debugging, we do not support code dump debugs in E2E. However I can provide some general guidance.

I recommend you to build and then walk through all lines of code in the sci_ex1_loopback.c example and see if there are any configuration items you are missing.

You can also compare the SCIA registers against your own to see if anything is configured differently.

NOTE: I tested the same setup on LaunchPad with the default sci_ex1_loopback.c example, and only modified to disable loopback and it works correctly without issues.

Regards,

Vince

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TMS320F2800137: serial Communication