RT1052 (5) PWM

xutong

RT1052 (5) PWM [复制链接]

 

在mcuXpresso中，可以对PWM的时钟进行配置，从黄色框中可以看出来PWM1的时钟来源来自IPG。

图1：设置IPG时钟

CLOCK_SetDiv(kCLOCK_IpgDiv, 0x00); // Set IPG

设置时钟分频的函数

图2：PWM内部框图

图3：PWM 子模块框图

PWM的特性:

• 16 bits of resolution for center, edge-aligned, and asymmetrical PWMs //16bit 中心值计数，沿对齐模式，不对称模式 适用各种复杂工况 • Fractional PWM clock generation for enhanced resolution of the PWM period and duty cycle • PWM outputs that can operate as complementary pairs or independent channels // 可以使用PWM 做互补对称，或者独立通道 • Ability to accept signed numbers for PWM generation • Independent control of both edges of each PWM output • Support for synchronization to external hardware or other PWM //支持外部信号对内部的PWM做同步 • Double buffered PWM registers • Integral reload rates from 1 to 16 • Half cycle reload capability • Multiple output trigger events can be generated per PWM cycle via hardware // PWM可以触发各种事件 • Support for double switching PWM outputs • Fault inputs can be assigned to control multiple PWM outputs • Programmable filters for fault inputs • Independently programmable PWM output polarity • Independent top and bottom deadtime insertion • Each complementary pair can operate with its own PWM frequency and deadtime values • Individual software control for each PWM output • All outputs can be programmed to change simultaneously via a FORCE_OUT event • PWM_X pin can optionally output a third PWM signal from each submodule • Channels not used for PWM generation can be used for buffered output compare functions • Channels not used for PWM generation can be used for input capture functions • Enhanced dual edge capture functionality

图4：PWM0模块时钟来源框图

/* pwm default config * config->enableDebugMode = false; * config->enableWait = false; * config->reloadSelect = kPWM_LocalReload; * config->clockSource = kPWM_BusClock; * config->prescale = kPWM_Prescale_Divide_1; * config->initializationControl = kPWM_Initialize_LocalSync; * config->forceTrigger = kPWM_Force_Local; * config->reloadFrequency = kPWM_LoadEveryOportunity; * config->reloadLogic = kPWM_ReloadImmediate; * config->pairOperation = kPWM_Independent; * */

PWM default config 中配置时钟来源

typedef enum _pwm_clock_source { kPWM_BusClock = 0U, /*!< The IPBus clock is used as the clock */ kPWM_ExternalClock, /*!< EXT_CLK is used as the clock */ kPWM_Submodule0Clock /*!< Clock of the submodule 0 (AUX_CLK) is used as the source clock */ } pwm_clock_source_t;

PWM 可选的时钟来源

图5：PWM submodule 123的时钟来源

在PWM的demo程序里面有这么一段

图6：XBARA 片段

看的很迷茫，于是打开SDK API Refrence看看

图7：XBARA 相关函数描述

大概意思就是把pwm的fault(x)连接到高电平。程序如下所示

// 步骤2：新建PWM初始化函数 void RT1052_PWM_Init(void) {     pwm_signal_param_t pwmSignal[2];   //步骤3：设置pwm的时钟，pwm的时钟来自ipg //在这里设置ipg的分频 ，设置为0时候 CLOCK_SetDiv(kCLOCK_IpgDiv, 0x03); // Set IPG   XBARA_Init(XBARA1); XBARA_SetSignalsConnection(XBARA1, kXBARA1_InputLogicHigh, kXBARA1_OutputFlexpwm1Fault0); XBARA_SetSignalsConnection(XBARA1, kXBARA1_InputLogicHigh, kXBARA1_OutputFlexpwm1Fault1); XBARA_SetSignalsConnection(XBARA1, kXBARA1_InputLogicHigh, kXBARA1_OutputFlexpwm1234Fault2); XBARA_SetSignalsConnection(XBARA1, kXBARA1_InputLogicHigh, kXBARA1_OutputFlexpwm1234Fault3); /* pwm default config * config->enableDebugMode = false; * config->enableWait = false; * config->reloadSelect = kPWM_LocalReload; * config->clockSource = kPWM_BusClock; * config->prescale = kPWM_Prescale_Divide_1; * config->initializationControl = kPWM_Initialize_LocalSync; * config->forceTrigger = kPWM_Force_Local; * config->reloadFrequency = kPWM_LoadEveryOportunity; * config->reloadLogic = kPWM_ReloadImmediate; * config->pairOperation = kPWM_Independent; * */ pwm_config_t config; //使用default的配置 PWM_GetDefaultConfig(&config);   /* 修改默认配置参数 */ /*新值在上一个pwm周期输出结束之后加载到缓冲寄存器中*/ config.reloadLogic = kPWM_ReloadPwmFullCycle; /*PwmA 和 PwmB 作为互补通道，PwmA 作为主通道*/ config.pairOperation = kPWM_ComplementaryPwmA; config.prescale = kPWM_Prescale_Divide_128; config.enableDebugMode = true; // 使能DebugMode   //配置PWM1 PWM_Init(PWM1,kPWM_Module_0,&config);   /*配置pwm 参数*/ pwmSignal[0].pwmChannel = kPWM_PwmA; //指定pwm 通道 pwmSignal[0].level = kPWM_HighTrue; //设置输出极性 pwmSignal[0].dutyCyclePercent=20;//设置 pwm的占空比 pwmSignal[0].deadtimeValue = 0; //设定死区值 pwmSignal[1].pwmChannel = kPWM_PwmB; pwmSignal[1].level = kPWM_HighTrue; pwmSignal[1].dutyCyclePercent = 20; pwmSignal[1].deadtimeValue = 0;   /*设置pwm 参数，包括pwm 的频率 占空比，死区时间等*/ PWM_SetupPwm(PWM1, kPWM_Module_0, pwmSignal, 2,\ kPWM_SignedEdgeAligned, PWM_frequency_Hz,PWM_SRC_CLK_FREQ);   /*设置Set LDOK 位，将初始化参数加载到相应的寄存器*/ PWM_SetPwmLdok(PWM1, kPWM_Control_Module_0 , true); //开始发波 PWM_StartTimer(PWM1, kPWM_Control_Module_0 );   }

 

 

参考文档

野火RT1025 demo程序

NXP1052 RM2

NXP1052 SDK API Refrence

lugl4313820

NXP的功低还是非常好。

xutong

lugl4313820 发表于 2022-12-5 09:16 NXP的功低还是非常好。

这颗是老freescale的人做的

hunter4051

现在NXP的RT做的挺好的

xutong

hunter4051 发表于 2022-12-5 10:42 现在NXP的RT做的挺好的

用起来

xutong

PWM.7z (18.21 MB, 下载次数: 5)

2022-12-6 14:59 上传

点击文件名下载附件

xutong

上面是工程文件

xutong

要发更精确的的PWM波形  可以调用这个函数

/*!
 * brief Updates the PWM signal's dutycycle with 16-bit accuracy.
 *
 * The function updates the PWM dutycyle to the new value that is passed in.
 * If the dead time insertion logic is enabled then the pulse period is reduced by the
 * dead time period specified by the user.
 *
 * param base              PWM peripheral base address
 * param subModule         PWM submodule to configure
 * param pwmSignal         Signal (PWM A or PWM B) to update
 * param currPwmMode       The current PWM mode set during PWM setup
 * param dutyCycle         New PWM pulse width, value should be between 0 to 65535
 *                          0=inactive signal(0% duty cycle)...
 *                          65535=active signal (100% duty cycle)
 */
void PWM_UpdatePwmDutycycleHighAccuracy(
    PWM_Type *base, pwm_submodule_t subModule, pwm_channels_t pwmSignal, pwm_mode_t currPwmMode, uint16_t dutyCycle)

 

xutong

更新一下驱动子程序：

https://github.com/xutong-analog/fantasy/tree/main/RT1052/flexpwm