CCS/CC2650: How to add delay before call BIOS_start();

Tanapan Kaewjongprasit

Prodigy 80 points

Part Number: CC2650
Other Parts Discussed in Thread: ADS1292R, SYSBIOS

Tool/software: Code Composer Studio

I use CC2650 with TI-RTOS and BLE stack 2.2.x.

Is there a way to add delay, in millisecond, before call BIOS_start()?

If not, do you have any suggestion to make precise delay time with empty for loop?

For example, if I use delay like this. What's TICK_NUMBER_IN_US should I use?

void delayMillisec(uint32_t timeToDelay)
{
  for(uint32_t ms=0; ms<timeToDelay; ms++)
  {
    for(uint32_t us=0; us<TICK_NUMBER_IN_US; us++)
    {
      //Do nothing;
    }
  }
}

It's OK to use roughly delay time. Although, it would be nice if I can determine how much exacly clock was use in each interation and calculate to precise time in microsecond.

over 5 years ago

0 TER over 5 years ago

TI__Guru**** 317180 points

What is the background for adding delay in main before BIAS_start?

0 Tanapan Kaewjongprasit over 5 years ago in reply to TER

Prodigy 80 points

I want to initialize some SPI device and it require some delay timing.

0 Tanapan Kaewjongprasit over 5 years ago in reply to TER

Prodigy 80 points

I just realize that, taskInit_Fxn is call after BIAS_start. So, I can use Task_sleep() for miliisecondDelay.

Although, I still need microsecond delay, which called in HWI, for waiting SPI device to decode the command.

0 TER over 5 years ago in reply to Tanapan Kaewjongprasit

TI__Guru**** 317180 points

Most drivers require that you call BIOS_start() before you can use the driver since this function call start a number of clocks etc. This is true for the SPI driver.

Could you elaborate why you need a delay when using SPI?

0 Tanapan Kaewjongprasit over 5 years ago in reply to TER

Prodigy 80 points

I'm working with ADS1292R and it reqired to wait 4 t_clk to decode and execute byte command, which is 7.8125us for clk == 512 kHz.

0 TER over 5 years ago in reply to Tanapan Kaewjongprasit

TI__Guru**** 317180 points

Could I regard this as solved?

0 Tanapan Kaewjongprasit over 5 years ago in reply to TER

Prodigy 80 points

I found function CPUdelay() and it work very nice with 12tick per 1us. I wonder that clock of CC2650 is 24MHz, but why CPUdelay use 12tick per microsecond, I think it should be 24tick.

If above issue is relate to cpu clock divider, how to change the divider number and how to get that number?

Furthermore. I try using Task_sleep but it not work. I got error "unresolved symbol Task_sleep, first referenced in <whole-program>" and warning "function "Task_sleep" declared implicitly".

0 TER over 5 years ago in reply to Tanapan Kaewjongprasit

TI__Guru**** 317180 points

- CPUDelay: http://software-dl.ti.com/dsps/dsps_public_sw/sdo_sb/targetcontent/tirtos/2_21_01_08/exports/tirtos_full_2_21_01_08/products/cc26xxware_2_24_03_17272/doc/driverlib/group__cpu__api.html#ga6a8880327e662906b655bf709bf179e7

Task_sleep(): See if #include <ti/sysbios/knl/Task.h> does the trick.

Typically if you get the error you got you have forgotten to include one or more .h files.

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CCS/CC2650: How to add delay before call BIOS_start();