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cCR changes for nRF52 PwmOut implementation.

pull/2234/head
Andrzej Puzdrowski 2016-07-12 15:12:09 +02:00
parent 9f337875bb
commit 3519122760
1 changed files with 64 additions and 29 deletions
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93
hal/targets/hal/TARGET_NORDIC/TARGET_NRF5/TARGET_MCU_NRF52832/pwmout_api.c
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@ -47,19 +47,45 @@
#include "app_util_platform.h"
#include "nrf_drv_pwm.h"
#define MAX_PWM_PERIOD_US (0x7FFF << 3) // -> 7FFF (1_us/16) * 128
#define MAX_PWM_COUNTERTOP (0x7FFF) // 0x7FFF is the max of COUNTERTOP value for the PWM peripherial of the nRF52.
#define MAX_PWM_PERIOD_US (MAX_PWM_COUNTERTOP * 8) // PWM hw is driven by 16 MHz clock, hence the tick is 1_us/16,
// and 128 is the max prescaler value.
#define MAX_PWM_PERIOD_MS ((MAX_PWM_PERIOD_US / 1000) + 1) // approximations advance
#define MAX_PWM_PERIOD_S ((MAX_PWM_PERIOD_US / 1000000) + 1) // approximations advance
#define PWM_INSTANCE_COUNT 3
#ifdef PWM0_ENABLED
#define __PWM0_NUM 1
#else
#define __PWM0_NUM 0
#endif
#ifdef PWM1_ENABLED
#define __PWM1_NUM 1
#else
#define __PWM1_NUM 0
#endif
#ifdef PWM2_ENABLED
#define __PWM2_NUM 1
#else
#define __PWM2_NUM 0
#endif
#define PWM_INSTANCE_COUNT (__PWM0_NUM + __PWM1_NUM + __PWM2_NUM)
///> instances of nRF52 PWM driver
static nrf_drv_pwm_t m_pwm_driver[PWM_INSTANCE_COUNT] =
static const nrf_drv_pwm_t m_pwm_driver[PWM_INSTANCE_COUNT] =
{
#ifdef PWM0_ENABLED
NRF_DRV_PWM_INSTANCE(0),
#endif
#ifdef PWM1_ENABLED
NRF_DRV_PWM_INSTANCE(1),
#endif
#ifdef PWM2_ENABLED
NRF_DRV_PWM_INSTANCE(2)
#endif
};
typedef struct
@ -78,20 +104,26 @@ typedef struct
static pwm_t m_pwm[PWM_INSTANCE_COUNT] =
{
#ifdef PWM0_ENABLED
{.p_pwm_driver = NULL},
#endif
#ifdef PWM0_ENABLED
{.p_pwm_driver = NULL},
#endif
#ifdef PWM0_ENABLED
{.p_pwm_driver = NULL}
#endif
}; /// Array of internal PWM instances.
typedef struct
{
uint16_t period_hwu;
uint16_t duty_hwu;
uint16_t period_hwu; // unit related to pwm_clk
uint16_t duty_hwu; // unit related to pwm_clk
nrf_pwm_clk_t pwm_clk;
} pulsewidth_set_t; /// helper type for timing calculations
static void internal_pwmout_exe(pwmout_t *obj, bool new_period);
static void internal_pwmout_exe(pwmout_t *obj, bool new_period, bool initialization);
void pwmout_init(pwmout_t *obj, PinName pin)
{
@ -105,14 +137,14 @@ void pwmout_init(pwmout_t *obj, PinName pin)
obj->pwm_channel = i;
m_pwm[i].p_pwm_driver = &m_pwm_driver[i];
m_pwm[i].p_pwm_driver = (nrf_drv_pwm_t *) &m_pwm_driver[i];
m_pwm[i].signal.period_us = 200000; // 0.02 s
m_pwm[i].signal.duty_us = 100000;
m_pwm[i].signal.duty = (0.5);
m_pwm[i].signal.duty = 0.5f;
obj->pwm_struct = &m_pwm[i];
internal_pwmout_exe(obj, true);
internal_pwmout_exe(obj, true, true);
break;
}
@ -135,16 +167,16 @@ void pwmout_write(pwmout_t *obj, float percent)
{
percent = 0;
}
else if (percent > 100)
else if (percent > 1)
{
percent = 100;
percent = 1;
}
pwm_signal_t * p_pwm_signal = &(((pwm_t*)obj->pwm_struct)->signal);
p_pwm_signal->duty = percent / 100;
p_pwm_signal->duty = percent;
int us = (((int)p_pwm_signal->period_us) * percent) / 100;
int us = (((int)p_pwm_signal->period_us) * percent);
pwmout_pulsewidth_us(obj, us);
}
@ -153,7 +185,7 @@ float pwmout_read(pwmout_t *obj)
{
pwm_signal_t * p_pwm_signal = &(((pwm_t*)obj->pwm_struct)->signal);
return (float)p_pwm_signal->duty_us / (float)p_pwm_signal->period_us * 100;
return (float)p_pwm_signal->duty_us / (float)p_pwm_signal->period_us;
}
void pwmout_period(pwmout_t *obj, float seconds)
@ -209,7 +241,7 @@ void pwmout_period_us(pwmout_t *obj, int us)
p_pwm_signal->period_us = us;
internal_pwmout_exe(obj, true);
internal_pwmout_exe(obj, true, false);
}
void pwmout_pulsewidth(pwmout_t *obj, float seconds)
@ -263,7 +295,7 @@ void pwmout_pulsewidth_us(pwmout_t *obj, int us)
p_pwm_signal->duty_us = us;
p_pwm_signal->duty = us / p_pwm_signal->period_us;
internal_pwmout_exe(obj, false);
internal_pwmout_exe(obj, false, false);
}
@ -271,24 +303,24 @@ void pwmout_pulsewidth_us(pwmout_t *obj, int us)
static ret_code_t pulsewidth_us_set_get(int period_us, int duty_us, pulsewidth_set_t * const p_settings)
static ret_code_t pulsewidth_us_set_get(int period_hwu, int duty_hwu, pulsewidth_set_t * p_settings)
{
uint16_t div;
nrf_pwm_clk_t pwm_clk = NRF_PWM_CLK_16MHz;
for(div = 1; div <= 128 ; div <<= 1)
for(div = 1; div <= 128 ; div <<= 1) // 128 is the maximum of clock prescaler for PWM peripherial
{
if (0x7FFF >= period_us)
if (MAX_PWM_COUNTERTOP >= period_hwu)
{
p_settings->period_hwu = period_us; // unit [us/16 * div]
p_settings->duty_hwu = duty_us; // unit [us/16 * div]
p_settings->period_hwu = period_hwu; // unit [us/16 * div]
p_settings->duty_hwu = duty_hwu; // unit [us/16 * div]
p_settings->pwm_clk = pwm_clk;
return NRF_SUCCESS;
}
period_us >>= 1;
duty_us >>= 1;
period_hwu >>= 1;
duty_hwu >>= 1;
pwm_clk++;
}
@ -296,7 +328,7 @@ static ret_code_t pulsewidth_us_set_get(int period_us, int duty_us, pulsewidth_s
}
static void internal_pwmout_exe(pwmout_t *obj, bool new_period)
static void internal_pwmout_exe(pwmout_t *obj, bool new_period, bool initialization)
{
pulsewidth_set_t pulsewidth_set;
pwm_signal_t * p_pwm_signal;
@ -305,13 +337,13 @@ static void internal_pwmout_exe(pwmout_t *obj, bool new_period)
p_pwm_signal = &(((pwm_t*)obj->pwm_struct)->signal);
if (NRF_SUCCESS == pulsewidth_us_set_get(p_pwm_signal->period_us * 16,
p_pwm_signal->duty_us * 16,
if (NRF_SUCCESS == pulsewidth_us_set_get(p_pwm_signal->period_us * 16, // base clk for PWM is 16 MHz
p_pwm_signal->duty_us * 16, // base clk for PWM is 16 MHz
&pulsewidth_set))
{
p_pwm_driver = (((pwm_t*)obj->pwm_struct)->p_pwm_driver);
nrf_pwm_sequence_t seq =
const nrf_pwm_sequence_t seq =
{
.values.p_common = (nrf_pwm_values_common_t*) (((pwm_t*)obj->pwm_struct)->seq_values),
.length = 1,
@ -340,7 +372,10 @@ static void internal_pwmout_exe(pwmout_t *obj, bool new_period)
.step_mode = NRF_PWM_STEP_AUTO
};
nrf_drv_pwm_uninit(p_pwm_driver);
if (!initialization)
{
nrf_drv_pwm_uninit(p_pwm_driver);
}
ret_code = nrf_drv_pwm_init( p_pwm_driver, &config0, NULL);