CC2340R5: I want to process at 60Hz

Manabu Hashimoto

Part Number: CC2340R5

Tool/software:

I am using FreeRTOS on CC2340R5.
I want to process at 60Hz as accurately as possible.
However, since the xTaskDelayUntil function can only be specified in milliseconds, there will be a slight deviation.
How can I process at 60Hz as accurately as possible?

#define WAIT_MS (16)

void *mainThread(void *arg0)
{
    MyInitialize();

    TickType_t previousWakeTime;
    previousWakeTime = xTaskGetTickCount();
    while (1)
    {
        if (xTaskDelayUntil(&previousWakeTime, WAIT_MS) != pdTRUE)
        {
        }

        MyProcess();
    }
}

2 months ago

0 Tanguy Baltazart 2 months ago

TI__Intellectual 2880 points

Hi Manabu,

I suggest using one of the CC240R5's timers, I think the LGPT timer suits best your use case. Take look at the API documentation for more information.

You can also review the Timers section in the User's Guide for a detailed list of all available timers.

Regards,
Tanguy

0 Manabu Hashimoto 2 months ago in reply to Tanguy Baltazart

Prodigy 40 points

Thank you for your reply.

I forgot to mention it in the explanation, but I want to put it in standby mode while not processing.
Sorry.

According to the explanation in the Timers section, it looks like "Clock DPL (ClockP Module ?)" can be used.
I don't know if it will work because there isn't much example code, but I'll give it a try.

Best regards,

0 Manabu Hashimoto 2 months ago in reply to Manabu Hashimoto

Prodigy 40 points

Created using ClockP and SemaphoreP.
It has been confirmed that ClockP goes into standby mode.

[Link1]

However, I don't know if SemaphoreP will go into standby mode.
Will registering Power_idleFunc() as a semaphore callback put the device into standby mode?

[Link2] [Link3]

// https://software-dl.ti.com/simplelink/esd/simplelink_lowpower_f3_sdk/8.10.01.02/exports/docs/drivers/doxygen/html/_semaphore_p_8h.html
// https://software-dl.ti.com/simplelink/esd/simplelink_lowpower_f3_sdk/8.10.01.02/exports/docs/drivers/doxygen/html/_clock_p_8h.html

SemaphoreP_Params g_PeriodicSemaphoreParams;
SemaphoreP_Handle g_PeriodicSemaphoreHandle;
ClockP_Params g_PeriodicParams;
ClockP_Handle g_PeriodicHandle;

void PeriodicCallback(uintptr_t arg)
{
    SemaphoreP_post(g_PeriodicSemaphoreHandle);
}

bool PeriodicInitialize()
{
    SemaphoreP_Params_init(&g_PeriodicSemaphoreParams);
    g_PeriodicSemaphoreParams.mode = SemaphoreP_Mode_BINARY;
    g_PeriodicSemaphoreParams.callback = Power_idleFunc;
    g_PeriodicSemaphoreHandle = SemaphoreP_create(0, &g_PeriodicSemaphoreParams);
    if (g_PeriodicSemaphoreHandle == NULL)
    {
        return false;
    }

    ClockP_Params_init(&g_PeriodicParams);
    g_PeriodicParams.period = 16666;
    g_PeriodicParams.startFlag = true;
    g_PeriodicParams.arg = (uintptr_t)NULL;
    g_PeriodicHandle = ClockP_create(PeriodicCallback, 0, &g_PeriodicParams);
    if (g_PeriodicHandle == NULL)
    {
        return false;
    }

    return true;
}

void *mainThread(void *arg0)
{
    MyInitialize();
    PeriodicInitialize();

    while (1)
    {
        SemaphoreP_pend(g_PeriodicSemaphoreHandle, SemaphoreP_WAIT_FOREVER);
        MyProcess();
    }
}

Best regards,

+1 Tanguy Baltazart 2 months ago in reply to Manabu Hashimoto

TI__Intellectual 2880 points

Hi Manabu,

The semaphore will give the hand back to the RTOS scheduler and you should go back into standby mode, you don't have to register a callback for that.

Regards,
Tanguy

0 Manabu Hashimoto 2 months ago in reply to Tanguy Baltazart

Prodigy 40 points

Thank you for your reply.

I don't have an energy trace compatible debugger so I can't measure the current, but I'll connect a battery and see what happens for a while.
Thanks!

Best regards,

Bluetooth®︎

Bluetooth forum

CC2340R5: I want to process at 60Hz