AWRL6432: Question on FRAME_REF_TIMER

Chris Meng

Part Number: AWRL6432
Other Parts Discussed in Thread: AWR6843

Hi,

In SDK5.4, I found below code. What's the address of 0x5B000020 for? Is it a timer counter register? Is it a 32-bit timer? I want to know when it will be overflow and return to 0.

//The function reads the FRAME_REF_TIMER that runs free at 40MHz
uint32_t Cycleprofiler_getTimeStamp(void)
{
uint32_t *frameRefTimer;
frameRefTimer = (uint32_t *) 0x5B000020;
return *frameRefTimer;
}

Thanks,

Chris

over 1 year ago

0 Chris Meng over 1 year ago

TI__Mastermind 37706 points

Hi,

I also found below code. Does below code reset above timer? I think it will reset RTI and above timer seems not RTI.

//Reset The FrameTimer for next frame
HW_WR_REG32(CSL_APP_RCM_U_BASE + CSL_APP_RCM_BLOCKRESET2, 0x1c0);

Thanks,

Chris

0 Kristien Everett over 1 year ago in reply to Chris Meng

TI__Genius 13026 points

Hey Chris,

The address 0x5B000020 is the FRAME_REF_TIMER register and holds the current value of the Frame Reference Timer. The timer is a free running 32 bit up counter running on the XTAL clock (40 MHz), starting from 0 at device power-on and rolling over each time after reaching 2^32.

The code you have shown can be used to reset the frame reference timer.

Regards,

Kristien

0 Chris Meng over 1 year ago in reply to Kristien Everett

TI__Mastermind 37706 points

Kristine.

Thanks for your help.

Will the counter keep the value after recovering from deep sleep mode? I am wondering why we need reset it manually. Or is it only useful for lowpowercfg = 2?

Best regards,

Chris

0 Kristien Everett over 1 year ago in reply to Chris Meng

TI__Genius 13026 points

Hey Chris,

The counter should keep its value after recovering from deep sleep since the XTAL clock is powered down during deep sleep. It should be reset manually in preparation for the next frame to resync the timer to calculate CPU cycle processing time for DPCs or generate frames upon reaching the frame periodicity.

Regards,

Kristien

0 Chris Meng over 1 year ago in reply to Kristien Everett

TI__Mastermind 37706 points

Kristien,

Do you mean the FRAME_REF_TIMER is used by FECSS for frame period timing?

I don't see such manual reset is needed in TI other mmwave sensor, like AWR6843.

Thanks,

Chris

0 Kristien Everett over 1 year ago in reply to Chris Meng

TI__Genius 13026 points

Hey Chris,

It is not used for frame period timing but rather to keep track of CPU cycle processing time when running most DPCs - see CycleCounterP_getCount32 function calls in files like classifier_demo.c. It can also be used for keeping track of the number of frames by iterating the frame count register (0x5B000028), but this is not utilized in our demos.

Regards,

Kristien

0 Chris Meng over 1 year ago in reply to Kristien Everett

TI__Mastermind 37706 points

Kristien，

So it is not related to RF timing and it is not MUST to resect. If customer didn't use tracker, it can keep run freely, right?

Thanks,

Chris

+1 Kristien Everett over 1 year ago in reply to Chris Meng

TI__Genius 13026 points

Hey Chris,

It is not related to RF timing and does not need to be reset. It can keep running freely.

Regards,

Kristien

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AWRL6432: Question on FRAME_REF_TIMER