Demo_PWM_同一个周期内立即更新占空比

qinzhao

背景
特殊应用场合出现同一个周期内，更新两次占空比，SDK自带DEMO会更新不进去
需求
芯片系列：MC0，MD，ME，LE
功能需求描述
特殊应用场合出现同一个周期内，更新两次占空比，无法更新
代码包：MCAL x.x.x/SDK x.x.x/RegCode
编译器：IAR/Keil/Gcc
解决方案描述
1.模拟同一个周期内多次更新占空比，去掉原demo里的两次更新占空比之间的延时
[图片]
此时PWM输出为第一次占空比设置的0%占空比。
2.将原来regisiter loading Opportunity配置的synchronized with counter matching MOD改为synchronized with register loading trigger source。
示例说明
2.将PWM设置为软触发更新
[图片]
3.在代码中将eTMR_DRV_SetLdok()函数改为eTMR_DRV_SyncWithSoftTrigger(ETMR_INST)

int main(void)
{
    /* USER CODE BEGIN 1 */
    /* USER CODE END 1 */ 
    Board_Init();
    /* USER CODE BEGIN 2 */
    /* PWM is generated when eTMR enable, the duty cycle is configured in the initial function */
    eTMR_DRV_Enable(ETMR_INST);
    OSIF_TimeDelay(10);

    /* The following code shows how to switch the different duty cycle */
    /* channel 2 duty cycle is 50% */
    eTMR_DRV_UpdatePwmChannel(ETMR_INST, ETMR_CHANNEL_INDEX0, 0x4000U, 0);
    /* channel 3 duty cycle is 75% */
    eTMR_DRV_UpdatePwmChannel(ETMR_INST, ETMR_CHANNEL_INDEX1, 0x6000U, 0);
    eTMR_DRV_SetLdok(ETMR_INST);
    OSIF_TimeDelay(10);

    /* channel 2 duty cycle is 100%, here is the workaround for 100% duty cycle
     * when channel is right align, value0 is configured as 0
     */
    g_etmrBase[ETMR_INST]->CH[ETMR_CHANNEL_INDEX0].VAL0 = 0;
    g_etmrBase[ETMR_INST]->CH[ETMR_CHANNEL_INDEX0].VAL1 = g_etmrBase[ETMR_INST]->MOD + 1;
    /* channel 3 duty cycle is 100% 
     * when channel is left/center/asymmetrical align, value0 is configured as 1
     */
    g_etmrBase[ETMR_INST]->CH[ETMR_CHANNEL_INDEX1].VAL0 = 1;
    g_etmrBase[ETMR_INST]->CH[ETMR_CHANNEL_INDEX1].VAL1 = g_etmrBase[ETMR_INST]->MOD + 1;
    eTMR_DRV_SetLdok(ETMR_INST);
    OSIF_TimeDelay(10);

    /* channel 2 duty cycle is 0 */
    eTMR_DRV_UpdatePwmChannel(ETMR_INST, ETMR_CHANNEL_INDEX0, 0, 0);
    /* channel 3 duty cycle is 0 */
    eTMR_DRV_UpdatePwmChannel(ETMR_INST, ETMR_CHANNEL_INDEX1, 0, 0);
    ***eTMR_DRV_SyncWithSoftTrigger(ETMR_INST);***
    //OSIF_TimeDelay(10);

    /* channel 2 duty cycle is 0x6000 */
    eTMR_DRV_UpdatePwmChannel(ETMR_INST, ETMR_CHANNEL_INDEX0, 0x6000U, 0);
    /* channel 3 duty cycle is 0x4000 */
    eTMR_DRV_UpdatePwmChannel(ETMR_INST, ETMR_CHANNEL_INDEX1, 0x4000U, 0);
    ***eTMR_DRV_SyncWithSoftTrigger(ETMR_INST);***
    /* USER CODE END 2 */

    /* Infinite loop */
    /* USER CODE BEGIN WHILE */
    while (1)
    {
        /* USER CODE END WHILE */
        /* USER CODE BEGIN 3 */
    }
    /* USER CODE END 3 */
}

可以输出最新的更新的占空比值，不再需要等到COUNTER值等于MOD值更新。
输出波形:
[图片]
5. 工程代码
8b54813e-6ed9-4df8-9464-81756d2f7667-Etmr_Pwm_Demo.zip

z1009591161

通过Ozone看占空比寄存器，此方法确实可以实现在一个周期内更改两次占空比，实际输出占空比为最后一次更改的占空比。

qinzhao

在示例说明里，增加YCT配置PWM软触发的图片：

TungDo

qinzhao Hi there, could you please give me the link of this configure tool?

qinzhao

帖子附件里有，下面是链接：
https://yt-static-media.oss-cn-hangzhou.aliyuncs.com/nodebb/24/e818fe45-5516-4885-a8ad-225aeb4c86ae.zip

qinzhao

The link in pdf.云途开发生态介绍.pdf

TungDo

qinzhao do you have another version in english?

TungDo

qinzhao many thanks for your support!

qinzhao

download link:https://account.ytmicro.com/#/login,
After registering and logging in, you can download it.

TungDo

qinzhao Do I need to pay any fees to use the YTC tool?

qinzhao

ytc tools are free

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Demo_PWM_同一个周期内立即更新占空比

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