Enabled TIM1 for PWM

This commit is contained in:
Thomas Kolb 2016-08-05 20:48:36 +02:00
parent 99447b3454
commit e485e23038
1 changed files with 30 additions and 51 deletions

View File

@ -12,12 +12,16 @@
#include "lcd.h"
#include "debug.h"
#define CONV_PWM_MAX 960
#define TIM_CH_CONV TIM_OC1
#define TIM_CH_BOOTSTRAP TIM_OC2
volatile int wait_frame = 1;
#define ADC_NUM_CHANNELS 3
volatile uint16_t adc_values[ADC_NUM_CHANNELS];
static void init_gpio(void)
{
// Set up UART TX on PB6 for debugging
@ -42,7 +46,6 @@ static void init_gpio(void)
static void init_clock(void)
{
/* Set STM32 to 48 MHz. */
// DANGER WARNING: ABP Clock is sysclk/2!
// Relevant for Timers
//rcc_clock_setup_in_hse_8mhz_out_48mhz();
rcc_clock_setup_in_hsi_out_48mhz();
@ -57,6 +60,9 @@ static void init_clock(void)
// enable TIM3 for scheduling
rcc_periph_clock_enable(RCC_TIM3);
// enable TIM1 for PWM generation
rcc_periph_clock_enable(RCC_TIM1);
// enable ADC1 clock
rcc_periph_clock_enable(RCC_ADC1);
@ -66,67 +72,40 @@ static void init_clock(void)
static void init_timer(void)
{
#if 0
// global interrupt config
nvic_enable_irq(NVIC_TIM1_UP_IRQ);
nvic_enable_irq(NVIC_TIM4_IRQ);
// *** TIM1 ***
// Generic scheduling
// Configure channels 1 and 2 for PWM (-> Pins PA8, PA9)
// Ch1 = Buck converter switch, Ch2 = bootstrap pulse
timer_reset(TIM1);
// - upcounter
// - clock: CK_INT
// - only overflow generates update interrupt
TIM1_CR1 |= TIM_CR1_URS;
// defaults for TIM_CR2
// enable update interrupt
TIM1_DIER |= TIM_DIER_UIE;
// prescaler
TIM1_PSC = 71; // count up by 1 every 1 us
// auto-reload (maximum value)
TIM1_ARR = 999; // overflow every 1 ms
// 48 kHz interrupt frequency
// TIM1_PSC = 24; // count up by 1 every 208.33 ns
// TIM1_ARR = 99; // multiply interval by 100 -> 20.833 us
// GO!
TIM1_CR1 |= TIM_CR1_CEN;
// *** TIM4 ***
// Configure channels 1 and 2 for PWM (-> Pins PB6, PB7)
// used for the boost converter switching
timer_reset(TIM4);
timer_set_mode(TIM4, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP);
timer_set_mode(TIM1, TIM_CR1_CKD_CK_INT, TIM_CR1_CMS_EDGE, TIM_CR1_DIR_UP);
// set up PWM channels
timer_set_oc_mode(TIM4, TIM_OC1, TIM_OCM_PWM1);
timer_enable_oc_output(TIM4, TIM_OC1);
timer_enable_oc_preload(TIM4, TIM_OC1);
timer_set_oc_polarity_high(TIM4, TIM_OC1);
timer_set_oc_mode(TIM1, TIM_CH_CONV, TIM_OCM_PWM1);
timer_enable_oc_output(TIM1, TIM_CH_CONV);
timer_enable_oc_preload(TIM1, TIM_CH_CONV);
timer_set_oc_polarity_high(TIM1, TIM_CH_CONV);
timer_set_oc_mode(TIM4, TIM_OC2, TIM_OCM_PWM1);
timer_enable_oc_output(TIM4, TIM_OC2);
timer_enable_oc_preload(TIM4, TIM_OC2);
timer_set_oc_polarity_low(TIM4, TIM_OC2);
timer_set_oc_mode(TIM1, TIM_CH_BOOTSTRAP, TIM_OCM_PWM1);
timer_enable_oc_output(TIM1, TIM_CH_BOOTSTRAP);
timer_enable_oc_preload(TIM1, TIM_CH_BOOTSTRAP);
timer_set_oc_polarity_low(TIM1, TIM_CH_BOOTSTRAP);
timer_set_oc_value(TIM1, TIM_CH_CONV, 0); // no PWM by default
timer_set_oc_value(TIM1, TIM_CH_BOOTSTRAP, 0); // no PWM by default
// wanted: 50 kHz / 20 us period
// system clock: 48 MHz
// => 960 clock cycles / period = CONV_PWM_MAX
// prescaler
timer_set_prescaler(TIM4, AUDIO_PWM_PRESCALER - 1);
timer_set_prescaler(TIM1, 0); // Timer runs at system clock
// auto-reload value
timer_set_period(TIM4, AUDIO_PWM_PERIOD - 1); // -> PWM frequency = 120e6 / prescaler / period
timer_set_period(TIM1, CONV_PWM_MAX - 1);
// enable update interrupt (triggered on timer restart)
timer_enable_irq(TIM4, TIM_DIER_UIE);
//timer_enable_irq(TIM1, TIM_DIER_UIE);
// GO!
timer_enable_counter(TIM4);
#endif
// *** TIM3 ***
// used for the 1-millisecond system tick
timer_reset(TIM3);