TMS320F28069M: Loss of PIE Group1 (Timer 0) Interrupt during Heavy SCI Rx

stomp

Part Number: TMS320F28069M

Hi,

I have a strange issue, that I am sure is just code, but really could use some help figuring it out.

I have Timer0 configured to generate 10 ms interrupts. I'm not doing anything too heavy in the interrupt, and upon leaving the interrupt I'm clearing the Timer0 interrupt flag and also doing a PIEACK to PIE Group1.

I have SCIB setup in FIFO mode, and I have RxFIFO Int enabled. In the FIFO routine I check the error status, queue up any data and upon leaving I clear RxFIFO Overflow, RxFIFO Int and PIEACK to PIE Group9.

Both of these systems work well in separate verification projects, but when joined together I see some issues.

I loose Timer 0 Interrupts while sending data to the SCIB UART. If I send a small amount (~8 bytes) no worries with T0. If I send a large amount at full speed I loose Timer0 somewhere in between.

Maybe I'm not too familiar with the interrupt functionality, but from the register window, when the error occurs, I see the Timer0 IE and IF bits set, I can see PIEER1 and PIEIFR1 bit 6 set (Timer0) but at the same time I can see PIEACK bit 1 set, and its not being cleared.

My understanding is that writing a 1 to PIEACK.x should clear it.

Any suggestions?

Thanks.

Stomp!.

over 7 years ago

0 Ken Schachter over 7 years ago

TI__Genius 17315 points

Stomp,

Please double check that at the very beginning of your ISR (not at the end) you have PIEACK:

//---------------------------------------------------------------------
interrupt void TINT0_ISR(void) // PIE1.7 @ 0x000D4C TINT0 (CPU TIMER 0)
{
PieCtrlRegs.PIEACK.all = PIEACK_GROUP1; // Must acknowledge the PIE group

// YOUR ISR GOES HERE

}

//---------------------------------------------------------------------
interrupt void SCIRXINTB_ISR(void) // PIE9.3 @ 0x000DC4 SCIRXINTB (SCI-B)
{
PieCtrlRegs.PIEACK.all = PIEACK_GROUP9; // Must acknowledge the PIE group

// YOUR ISR GOES HERE

}

//---------------------------------------------------------------------
interrupt void SCITXINTB_ISR(void) // PIE9.4 @ 0x000DC6 SCITXINTB (SCI-B)
{
PieCtrlRegs.PIEACK.all = PIEACK_GROUP9; // Must acknowledge the PIE group

// YOUR ISR GOES HERE

}

//---------------------------------------------------------------------

I hope this helps. If this answers your question, please click the green "Verified Answer" button. Thanks.

- Ken

0 stomp over 7 years ago in reply to Ken Schachter

Genius 4675 points

Thanks Ken,

This was the issue. I was ack'ing the PIE at the end of the routine, not at the beginning.

Appreciate the help, such as simple solution to a painful problem.

Cheers.
Stomp!

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TMS320F28069M: Loss of PIE Group1 (Timer 0) Interrupt during Heavy SCI Rx