TMS320F28035: CLA Task Clock Cycle

Merih Eren

Part Number: TMS320F28035
Other Parts Discussed in Thread: CONTROLSUITE

Dear all,

Is there any way to learn how many clock cycles last a CLA task? For an ISR which is fun by CPU, I store the time at the beginning of the ISR and at the end of the ISR and I subtract the first time from the second time, In this way, I can find how many clock cycles last that ISR. However, in CLA task, when I apply the same procedure, it gives me nothing.

I would be appreciated if someone show me a way to solve this. Thank you in advanced.

Kind Regards,

Merih.

over 8 years ago

0 Ibrahim Kolbas over 8 years ago

Intellectual 340 points

interrupt void EPWM1_INT_ISR() // Try this :
{ STRT_CHRONO; // Memorize timer count at start ( e.g CpuTimer1Regs.TIM.all)
Cla1ForceTask4(); // This is where CLA-Task4 starts
....
}

interrupt void CLA1_INT4_ISR() // This is where CLA-Task4 ends
{ STOP_CHRONO; // Memorize timer count at stop and use the difference
...
}

0 Merih Eren over 8 years ago in reply to Ibrahim Kolbas

Intellectual 440 points

Hi Ibrahim,

Thank you for the reply.

I use "clk1 = CpuTimer0Regs.TIM.all;" line to store the time both in CPU and CLA. I get a value in CPU interrupt but CLA gives me nothing. I think this is because of that I am using CPU timer both in CPU and CLA. Which timer should I use for CLA?

Thank you again.

Kind Regards,
Merih

0 Vishal_Coelho over 8 years ago in reply to Merih Eren

TI__Mastermind 20850 points

Hi Merih,

The CLA on the 28035 does not have access to the timers, but the idea is a correct one. You will have to use the timer from a spare EPwm module. The procedure for this is documented in the firmware user's guide (ti/controlsuite/device_support/f2803x/version/doc/...UG.pdf, section 5.7). Here is the exerpt

5.7.2 Benchmarking
The CLA does not support the clock function and therefore it is not possible to get a direct cycle
count of a particular task. The user can configure the time base module on an ePWM to keep track
of the execution time of a task
Setup the time base of ePWM1(or any ePWM) to run at SYSCLKOUT in the up-count mode as
shown below:
void InitEPwm(void)
{
// Setup TBCLK
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP; // Count up
EPwm1Regs.TBPRD = 0xFFFF; // Set timer period
EPwm1Regs.TBCTL.bit.PHSEN = TB_DISABLE; // Disable phase loading
EPwm1Regs.TBPHS.half.TBPHS = 0x0000; // Phase is 0
EPwm1Regs.TBCTR = 0x0000; // Clear counter
EPwm1Regs.TBCTL.bit.HSPCLKDIV = TB_DIV1; // Clock ratio to SYSCLKOUT
EPwm1Regs.TBCTL.bit.CLKDIV = TB_DIV1;
}

Proceed to define two macros READ_CLOCK and RESTART_CLOCK, the former to freeze the
ePWM timer and copy the elapsed time to a variable, and the latter to restart the ePWM timer.
#define READ_CLOCK(X) __meallow();\
EPwm1Regs.TBCTL.bit.CTRMODE = TB_FREEZE;\
X = EPwm1Regs.TBCTR;\
__medis();
#define RESTART_CLOCK __meallow();\
EPwm1Regs.TBCTL.bit.CTRMODE = TB_FREEZE;\
EPwm1Regs.TBCTR = 0;\
EPwm1Regs.TBCTL.bit.CTRMODE = TB_COUNT_UP;\
__medis();
Define a variable e.g. ulCycleCount to hold the cycle count
#pragma DATA_SECTION(ulCycleCount,"Cla1ToCpuMsgRAM");
unsigned long ulCycleCount;
Place the macro RESTART_CLOCK at the beginning of a task to restart the ePWM timer and place
READ_CLOCK at the end of the task to read the value of the timer. The elapsed time will be give
you the cycle count plus a minimal overhead from the two macros
__interrupt void Cla1Task1 ( void )
{
//Local Variables
float a;
__mdebugstop();
RESTART_CLOCK;
a = 10;
...
...
...
READ_CLOCK(ulCycleCount);
}

0 Ibrahim Kolbas over 8 years ago in reply to Merih Eren

Intellectual 340 points

Hi Melih;
CLA´s access to resources is limited; that´s the reason why you get ´nothing´ (zero) when you try to read timer from the CLA.
The example-code should run 'ONLY ON CPU'. There is no access necessary from within CLA!
// ------------------------------------------------------------------------------------------------------------------------------------------
// -- Do not forget to correctly set up an enable both interrupts ----
//
interrupt void EPWM1_INT_ISR() // Try this :
{ STRT_CHRONO; // Memorize timer count at start ( e.g CpuTimer1Regs.TIM.all)
Cla1ForceTask4(); // This is where CLA-Task4 starts
....
}

interrupt void CLA1_INT4_ISR() // This is where CLA-Task4 ends
{ STOP_CHRONO; // Memorize SAME timer count ( e.g CpuTimer1Regs.TIM.all) at stop and use the difference
...
}
// ------------------------------------------------------------------------------------------------------------------------------------------
Regards

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TMS320F28035: CLA Task Clock Cycle