tkl_pwm | PWM Driver

Brief Description

PWM (Pulse Width Modulation) is an effective technology that uses the digital output of a microprocessor to control analog circuits.

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As shown in the figure above, a PWM waveform with a pulse period of 10ms: the first period has a high level of 7ms (duty cycle 70%); the second period has a high level of 4ms (duty cycle 40%). By adjusting the duty cycle value of the high level, the size of the analog output value can be changed.

API Description

tkl_pwm_init

OPERATE_RET tkl_pwm_init(TUYA_PWM_NUM_E ch_id, const TUYA_PWM_BASE_CFG_T *cfg);

• Function Description:

  • Initializes the corresponding PWM instance through the port number and basic configuration, returning the initialization result.

• Parameters:

  • ch_id: Channel number.

  • cfg: PWM basic configuration, including output polarity, duty cycle, and frequency.

    typedef struct {
        TUYA_PWM_POLARITY_E polarity;
        TUYA_PWM_COUNT_E    count_mode;
        //pulse duty cycle = duty / cycle; exp duty = 5000,cycle = 10000; pulse duty cycle = 50%
        uint32_t              duty;
        uint32_t              cycle;
        uint32_t              frequency;  // (bet: Hz)
    } TUYA_PWM_BASE_CFG_T;

    polarity:

    Name	Definition	Remarks
    TUYA_PWM_NEGATIVE	PWM low-level output
    TUYA_PWM_POSITIVE	PWM high-level output

    count_mode:

    Counting mode, with TUYA_PWM_CNT_UP and TUYA_PWM_CNT_UP_AND_DOWN as options.

    duty:

    Duty cycle, used with cycle, output = duty / cycle.

    cycle:

    Period, or granularity, output = duty / cycle.

    frequency:

    Output frequency, in Hz.

• Return Value:

  • OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_deinit

OPERATE_RET tkl_pwm_deinit(TUYA_PWM_NUM_E ch_id);

• Function Description:
  • Deinitializes the PWM instance.
  • This interface stops any ongoing transmission of the PWM instance (if any) and releases related software and hardware resources.
• Parameters:
  • ch_id: Channel number.
• Return Value:
  • OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_start

OPERATE_RET tkl_pwm_start(TUYA_PWM_NUM_E ch_id);

• Function Description:
  • Starts PWM.
• Parameters:
  • ch_id: Channel number.
• Return Value:
  • OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_stop

OPERATE_RET tkl_pwm_stop(TUYA_PWM_NUM_E ch_id);

• Function Description:
  • Stops PWM.
• Parameters:
  • port: Port number.
• Return Value:
  • OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_multichannel_start

OPERATE_RET tkl_pwm_multichannel_start(TUYA_PWM_NUM_E *ch_id, uint8_t num);

• Function Description:
  • Simultaneously starts multiple channel PWMs for combined output, used in scenarios with strict timing requirements.
• Parameters:
  • ch_id: List of channel numbers, array.
  • num: Number of channels to start.
• Return Value:
  • OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_multichannel_stop

OPERATE_RET tkl_pwm_multichannel_stop(TUYA_PWM_NUM_E *ch_id, uint8_t num);

• Function Description:
  • Simultaneously stops multiple channel PWMs for combined output, used in scenarios with strict timing requirements.
• Parameters:
  • ch_id: List of channel numbers, array.
  • num: Number of channels to stop.
• Return Value:
  • OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_info_set

OPERATE_RET tkl_pwm_info_set(TUYA_PWM_NUM_E ch_id, const TUYA_PWM_BASE_CFG_T *info);

• Function Description:
  • Resets PWM configuration parameters, allowing dynamic modification of the configuration after PWM start, and then restarts.
• Parameters:
  • ch_id: Channel number.
  • info: PWM basic configuration, including output polarity, duty cycle, frequency. The structure parameters are described above.
• Return Value:
  • Error code, OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_info_get

OPERATE_RET tkl_pwm_info_get(TUYA_PWM_NUM_E ch_id, TUYA_PWM_BASE_CFG_T *info);

• Function Description:
• Parameters:
  • ch_id: Channel number.
  • info: PWM basic configuration, including output polarity, duty cycle, frequency. The structure parameters are described above.
• Return Value:
  • Error code, OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_cap_start

OPERATE_RET tkl_pwm_cap_start(TUYA_PWM_NUM_E ch_id, const TUYA_PWM_CAP_IRQ_T *cfg);

• Function Description:

  • Enables PWM input capture mode.

• Parameters:

  • ch_id: Channel number.

  • cfg: PWM input capture configuration, as detailed below.

    cap_mode:

    Name	Definition	Remarks
    TUYA_PWM_CAPTURE_MODE_ONCE	Single trigger mode
    TUYA_PWM_CAPTURE_MODE_PERIOD	Multiple trigger mode

    trigger_level:

    Name	Definition	Remarks
    TUYA_PWM_NEGATIVE	Trigger signal is falling edge
    TUYA_PWM_POSITIVE	Trigger signal is rising edge

    clk:

    Sampling clock for captured signal.

    cb:

    Callback function for captured signal, as follows:

    typedef void(*TUYA_PWM_IRQ_CB)(TUYA_PWM_NUM_E port, TUYA_PWM_CAPTURE_DATA_T data, void *arg);

    typedef struct {
        uint32_t      cap_value;            /* Captured data */
        TUYA_PWM_POLARITY_E cap_edge;     /* Capture edge, TUYA_PWM_NEGATIVE:falling edge, TUYA_PWM_POSITIVE:rising edge */
    } TUYA_PWM_CAPTURE_DATA_T;

    arg:

    Callback function parameters.

• Return Value:

  • Error code, OPRT_OK for success, other values please refer to the file tuya_error_code.h.

tkl_pwm_cap_stop

OPERATE_RET tkl_pwm_cap_stop(TUYA_PWM_NUM_E ch_id);

• Function Description:
  • Disables PWM input capture mode.
• Parameters:
  • ch_id: Channel number.
• Return Value:
  • Error code, OPRT_OK for success, other values please refer to the file tuya_error_code.h.

PWM Example

void tuya_pwm_test(void)
{
    OPERATE_RET ret;
    TUYA_PWM_BASE_CFG_T cfg = {.polarity = TUYA_PWM_POSITIVE,\
                       .duty = 1000,
                       .cycle = 10000,
                       .frequency = 1000};
    ret = tkl_pwm_init(TUYA_PWM_NUM_0, &cfg);
    if (ret != OPRT_OK) {
        //fail
        return;
    }
    ret = tkl_pwm_start(TUYA_PWM_NUM_0);
    if (ret != OPRT_OK) {
        //fail
        return;
    }
    tkl_system_delay(5000);
    ret = tkl_pwm_info_get(TUYA_PWM_NUM_0, &cfg);
    if (ret != OPRT_OK) {
        //fail
        return;
    }
    if(cfg.duty !=5000){
        cfg.duty =5000;
    }
    ret = tkl_pwm_info_set(TUYA_PWM_NUM_0, &cfg);
    //delay
    tkl_system_delay(5000);
    ret = tkl_pwm_stop(TUYA_PWM_NUM_0);
    if (ret != OPRT_OK) {
        //fail
        return;
    }
    ret = tkl_pwm_deinit(TKL_PWM1_CH);
    if (ret != OPRT_OK) {
        //fail
        return;
    }
}