LibXR::HPMPWM Class Reference

HPM 平台 PWM 驱动实现 / PWM driver implementation for HPM platform. More...

#include <hpm_pwm.hpp>

Inheritance diagram for LibXR::HPMPWM:

Collaboration diagram for LibXR::HPMPWM:

Public Types
enum class	Polarity : uint8_t { NORMAL , INVERTED }
	输出极性 / Output polarity. More...

Public Member Functions
	HPMPWM (LibXRHpmPwmType *pwm, clock_name_t clock, uint8_t pwm_index, uint8_t cmp_index, Polarity polarity)
	构造 HPM PWM 对象 / Construct an HPM PWM object.
ErrorCode	SetDutyCycle (float value) override
	设置占空比 / Set PWM duty cycle.
ErrorCode	SetConfig (Configuration config) override
	配置 PWM 频率 / Configure PWM frequency.
ErrorCode	Enable () override
	启动 PWM 输出 / Start PWM output.
ErrorCode	Disable () override
	停止 PWM 输出 / Stop PWM output.
Public Member Functions inherited from LibXR::PWM

Detailed Description

HPM 平台 PWM 驱动实现 / PWM driver implementation for HPM platform.

Definition at line 30 of file hpm_pwm.hpp.

Member Enumeration Documentation

Polarity

enum class LibXR::HPMPWM::Polarity : uint8_t

strong

输出极性 / Output polarity.

Enumerator
NORMAL	不反相 / Not inverted.
INVERTED	反相输出 / Inverted output.

Definition at line 34 of file hpm_pwm.hpp.

  {
    NORMAL,   
    INVERTED  
  };

Constructor & Destructor Documentation

HPMPWM()

HPMPWM::HPMPWM	(	LibXRHpmPwmType *	pwm,
		clock_name_t	clock,
		uint8_t	pwm_index,
		uint8_t	cmp_index,
		Polarity	polarity )

构造 HPM PWM 对象 / Construct an HPM PWM object.

构造 PWM 实例 / Construct PWM instance.

Parameters

pwm	PWM 外设基地址 / PWM peripheral base address.
clock	PWM 对应时钟源 / Clock source used by this PWM instance.
pwm_index	PWM 输出通道索引 / PWM output index.
cmp_index	与输出绑定的比较器索引 / Comparator index bound to the PWM output.
polarity	输出极性 / Output polarity.

Note

引脚复用和外设时钟由 BSP 在使用前配置（例如 HPM Pinmux Tool 生成的函数）， 驱动不调用板级 helper。 The BSP sets up the pin mux and the peripheral clock before use (for example with the functions generated by the HPM Pinmux Tool); the driver calls no board helper.

说明：

• 当芯片存在原生 PWM 外设时，pwm_ 按原生路径使用；
• 当芯片仅有 GPTMR 输出比较能力时，gptmr_ 走 fallback 路径。 Notes:
• If native PWM exists, pwm_ is used in native path.
• If only GPTMR compare output is available, gptmr_ is used as fallback.

Definition at line 24 of file hpm_pwm.cpp.

    : pwm_(pwm),
      gptmr_(reinterpret_cast<GPTMR_Type*>(pwm)),
      clock_(clock),
      pwm_index_(pwm_index),
      cmp_index_(cmp_index),
      invert_(polarity == Polarity::INVERTED),
      reload_(0),
      configured_(false)
{
}

Member Function Documentation

Disable()

ErrorCode HPMPWM::Disable ( )

overridevirtual

停止 PWM 输出 / Stop PWM output.

Returns

操作结果 / Operation result.

Implements LibXR::PWM.

Definition at line 184 of file hpm_pwm.cpp.

{
#if LIBXR_HPM_PWM_SUPPORTED
  pwm_stop_counter(pwm_);
#elif LIBXR_HPM_GPTMR_PWM_FALLBACK
  gptmr_stop_counter(gptmr_, pwm_index_);
#else
  return ErrorCode::NOT_SUPPORT;
#endif
  return ErrorCode::OK;
}

Enable()

ErrorCode HPMPWM::Enable ( )

overridevirtual

启动 PWM 输出 / Start PWM output.

Returns

操作结果 / Operation result.

Implements LibXR::PWM.

Definition at line 166 of file hpm_pwm.cpp.

{
  if (!configured_)
  {
    return ErrorCode::INIT_ERR;
  }
 
#if LIBXR_HPM_PWM_SUPPORTED
  pwm_start_counter(pwm_);
#elif LIBXR_HPM_GPTMR_PWM_FALLBACK
  gptmr_start_counter(gptmr_, pwm_index_);
#else
  return ErrorCode::NOT_SUPPORT;
#endif
 
  return ErrorCode::OK;
}

SetConfig()

ErrorCode HPMPWM::SetConfig ( Configuration config )

overridevirtual

配置 PWM 频率 / Configure PWM frequency.

Parameters

config

PWM 配置参数 / PWM configuration.

Returns

操作结果 / Operation result.

Implements LibXR::PWM.

Definition at line 80 of file hpm_pwm.cpp.

{
  if (config.frequency == 0u)
  {
    return ErrorCode::ARG_ERR;
  }
 
  const uint32_t clock_hz = clock_get_frequency(clock_);
 
  if (clock_hz == 0u)
  {
    return ErrorCode::INIT_ERR;
  }
 
  uint32_t reload = clock_hz / config.frequency;
  if (reload == 0u || reload > 0xFFFFFFu)
  {
    return ErrorCode::INIT_ERR;
  }
  reload_ = reload;
 
#if LIBXR_HPM_PWM_SUPPORTED
  pwm_stop_counter(pwm_);
 
  pwm_config_t pwm_config{};
  pwm_cmp_config_t cmp_config{};
 
  pwm_get_default_pwm_config(pwm_, &pwm_config);
  pwm_get_default_cmp_config(pwm_, &cmp_config);
 
  pwm_config.enable_output = true;
  pwm_config.invert_output = invert_;
  pwm_config.dead_zone_in_half_cycle = 0;
 
  pwm_set_reload(pwm_, 0, reload_);
  pwm_set_start_count(pwm_, 0, 0);
 
  cmp_config.mode = pwm_cmp_mode_output_compare;
  cmp_config.cmp = reload_ + 1;
  cmp_config.update_trigger = pwm_shadow_register_update_on_modify;
 
  if (pwm_setup_waveform(pwm_, pwm_index_, &pwm_config, cmp_index_, &cmp_config, 1) !=
      status_success)
  {
    return ErrorCode::INIT_ERR;
  }
 
  pwm_issue_shadow_register_lock_event(pwm_);
#elif LIBXR_HPM_GPTMR_PWM_FALLBACK
  if (gptmr_ == nullptr)
  {
    return ErrorCode::ARG_ERR;
  }
 
  const uint8_t reload_cmp_index = ResolveGptmrReloadCmpIndex(cmp_index_);
  if (reload_cmp_index == INVALID_CMP_INDEX)
  {
    return ErrorCode::ARG_ERR;
  }
 
  // 重新配置前先停计数器，避免切换参数时输出毛刺。
  // Stop counter before reconfiguration to avoid output glitches.
  gptmr_stop_counter(gptmr_, pwm_index_);
 
  gptmr_channel_config_t cfg;
  gptmr_channel_get_default_config(gptmr_, &cfg);
  cfg.mode = gptmr_work_mode_no_capture;
  cfg.cmp_initial_polarity_high = invert_;
  cfg.enable_cmp_output = true;
  cfg.reload = reload_;
  cfg.cmp[cmp_index_] = reload_ / 2u;
  cfg.cmp[reload_cmp_index] = reload_;
 
  if (gptmr_channel_config(gptmr_, pwm_index_, &cfg, false) != status_success)
  {
    return ErrorCode::INIT_ERR;
  }
  gptmr_channel_reset_count(gptmr_, pwm_index_);
#else
  return ErrorCode::NOT_SUPPORT;
#endif
 
  configured_ = true;
  return ErrorCode::OK;
}

SetDutyCycle()

ErrorCode HPMPWM::SetDutyCycle ( float value )

overridevirtual

设置占空比 / Set PWM duty cycle.

Parameters

value

占空比范围 [0.0, 1.0] / Duty cycle in range [0.0, 1.0].

Returns

操作结果 / Operation result.

Implements LibXR::PWM.

Definition at line 37 of file hpm_pwm.cpp.

{
  if (!configured_)
  {
    return ErrorCode::INIT_ERR;
  }
 
  if (value < 0.0f)
  {
    value = 0.0f;
  }
  else if (value > 1.0f)
  {
    value = 1.0f;
  }
 
#if LIBXR_HPM_PWM_SUPPORTED
  const float duty_percent = value * 100.0f;
  if (pwm_update_duty_edge_aligned(pwm_, cmp_index_, duty_percent) != status_success)
  {
    return ErrorCode::FAILED;
  }
#elif LIBXR_HPM_GPTMR_PWM_FALLBACK
  // GPTMR 比较值不允许落在 0 或 reload，避免输出退化成常高/常低。
  // Keep compare away from 0/reload to avoid constant-high/constant-low output.
  uint32_t cmp = static_cast<uint32_t>(static_cast<float>(reload_) * value);
  if (cmp == 0u)
  {
    cmp = 1u;
  }
  else if (cmp >= reload_)
  {
    cmp = reload_ - 1u;
  }
  gptmr_update_cmp(gptmr_, pwm_index_, cmp_index_, cmp);
#else
  (void)value;
  return ErrorCode::NOT_SUPPORT;
#endif
 
  return ErrorCode::OK;
}

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The documentation for this class was generated from the following files:

• driver/hpm/hpm_pwm.hpp
• driver/hpm/hpm_pwm.cpp