jaseg/olsndot
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

f4: proper float/int temp readings

Browse source
This commit is contained in:
Karl Palsson 2015-11-03 22:34:40 +00:00
parent 30e3339a94
commit 4a1f9d06d2
3 changed files with 50 additions and 41 deletions
Download patch file Download diff file Expand all files Collapse all files

1
rules.mk
View file

@ -92,6 +92,7 @@ TGT_CXXFLAGS += -Wextra -Wshadow -Wredundant-decls -Weffc++
TGT_LDFLAGS += -T$(LDSCRIPT) -L$(OPENCM3_DIR)/lib -nostartfiles
TGT_LDFLAGS += $(ARCH_FLAGS)
TGT_LDFLAGS += -specs=nano.specs
TGT_LDFLAGS += -u _printf_float
TGT_LDFLAGS += -Wl,--gc-sections
# OPTIONAL
#TGT_LDFLAGS += -Wl,-Map=$(PROJECT).map

84
tests/adc-power/adc-power.c
View file

@ -19,6 +19,28 @@
// TODO - stick this in libopencm3?
#define ARRAY_SIZE(a) (sizeof((a)) / sizeof((a)[0]))
// Still have some bad shit to deal with...
#if defined(STM32F3)
#define SAMPLE_TIME_BASIC ADC_SMPR1_SMP_19DOT5CYC
#elif defined(STM32F4)
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_28CYC
#define SAMPLE_TIME_TEMP ADC_SMPR_SMP_144CYC
#define SAMPLE_TIME_VREF SAMPLE_TIME_TEMP
#define ADC_CHANNEL_TEMP ADC_CHANNEL_TEMP_F40
#define SEPARATE_VREF 0
#elif defined(STM32L1)
#define SAMPLE_TIME_BASIC ADC_SMPR_SMP_24CYC
#define SAMPLE_TIME_TEMP ADC_SMPR_SMP_192CYC
#define SAMPLE_TIME_VREF SAMPLE_TIME_TEMP
#define SEPARATE_VREF 0
#else
#error "no sample time for your target yet?!"
#endif
#ifndef SEPARATE_VREF
#define SEPARATE_VREF 1
#endif
void adc_power_init(void)
{
@ -29,10 +51,12 @@ void adc_power_init(void)
rcc_adc_prescale(RCC_CFGR2_ADCxPRES_PLL_CLK_DIV_1, RCC_CFGR2_ADCxPRES_PLL_CLK_DIV_1);
adc_enable_regulator(ADC1);
adc_set_sample_time_on_all_channels(ADC1, ADC_SMPR1_SMP_19DOT5CYC);
adc_set_sample_time(ADC1, ADC_CHANNEL_TEMP, ADC_SMPR1_SMP_181DOT5CYC);
#else
rcc_periph_clock_enable(RCC_ADC1);
adc_set_sample_time_on_all_channels(ADC1, ADC_SMPR_SMP_28CYC);
adc_set_sample_time_on_all_channels(ADC1, SAMPLE_TIME_BASIC);
adc_set_sample_time(ADC1, ADC_CHANNEL_TEMP, SAMPLE_TIME_TEMP);
adc_set_sample_time(ADC1, ADC_CHANNEL_TEMP, SAMPLE_TIME_VREF);
#if 0
// DANGER DANGER! doing this without DMA is dum.
// but... we're busy polling, we should be right... right?
@ -45,7 +69,10 @@ void adc_power_init(void)
#endif
adc_enable_temperature_sensor();
#if (SEPARATE_VREF == 1)
adc_enable_vrefint();
#endif
/*
* We're going to setup a timer to run at top speed, so... "fast"
* but we don't actually care about the rate itself. We just
@ -68,28 +95,16 @@ static uint16_t read_adc_naiive(uint8_t channel)
return adc_read_regular(ADC1);
}
static uint16_t compensate_vref(uint16_t adc_count, uint16_t vref_count) {
uint32_t ret = adc_count * ST_VREFINT_CAL;
return (ret / vref_count);
static float adc_calc_tempf(unsigned int ts_v, unsigned int vref) {
float adjusted_vtemp = ts_v * ST_VREFINT_CAL * 1.0 / vref * 1.0;
float slope = (110-30) * 1.0 / (ST_TSENSE_CAL2_110C - ST_TSENSE_CAL1_30C) * 1.0;
return slope * (adjusted_vtemp - ST_TSENSE_CAL1_30C) + 30;
}
static int work_temp(unsigned int ts_v, unsigned int vref) {
// This is important! as the calibration values are give us a slope in mv/C
int raw_temp_mv = compensate_vref(ts_v, vref);
// millivolts gives millcentigrade
float slope = raw_temp_mv - (ST_TSENSE_CAL1_30C * 1.0) / (ST_TSENSE_CAL2_110 * 1.0) - ST_TSENSE_CAL1_30C;
int temp_mc = (110 - 30) * slope + 30.0;
return temp_mc / 10;
}
static float adc_calculate_temp(unsigned int ts_v) {
#if 0
float factor = (110-30) / ((ST_TSENSE_CAL1_30C * 1.0) - (ST_TSENSE_CAL2_110 * 1.0));
return (factor * (ts_v - ST_TSENSE_CAL2_110)) + 30.0;
#else
float factor = (110-30) / ((ST_TSENSE_CAL2_110 * 1.0) - (ST_TSENSE_CAL1_30C * 1.0));
return (factor * (ts_v - ST_TSENSE_CAL1_30C)) + 30.0;
#endif
static float adc_calc_tempi(uint16_t ts, uint16_t vref) {
int adjusted_vtemp = ts * ST_VREFINT_CAL / vref;
int slope = (110-30) / (ST_TSENSE_CAL2_110C - ST_TSENSE_CAL1_30C);
return slope * (adjusted_vtemp - ST_TSENSE_CAL1_30C) + 30;
}
void adc_power_task_up(void) {
@ -100,30 +115,23 @@ void adc_power_task_up(void) {
/* just for kicks, let's time some sequences too....
* I mean, we're going to do some conversions right? */
adc_set_single_conversion_mode(ADC1);
#if 0
uint8_t channels[2] = { 0, 1 };
adc_set_regular_sequence(ADC1, ARRAY_SIZE(channels), channels);
TIM_CNT(TIMER) = 0;
adc_start_conversion_regular(ADC1);
while (!adc_eoc(ADC1));
unsigned int v1 = adc_read_regular(ADC1);
while (!adc_eoc(ADC1));
unsigned int v2 = adc_read_regular(ADC1);
unsigned int tconv = TIM_CNT(TIMER);
#else
TIM_CNT(TIMER) = 0;
unsigned int v1 = read_adc_naiive(1);
unsigned int v5 = read_adc_naiive(5);
unsigned int temp_adc = read_adc_naiive(ADC_CHANNEL_TEMP);
unsigned int vref_adc = read_adc_naiive(ADC_CHANNEL_VREF);
// TODO - use vref to adjust temp_adc for non-3v readings!
float temp = adc_calculate_temp(temp_adc);
int tempi = 100 * temp;
unsigned int tconv = TIM_CNT(TIMER);
#endif
TIM_CNT(TIMER) = 0;
float tempf = adc_calc_tempf(temp_adc, vref_adc);
int tconvf = TIM_CNT(TIMER);
TIM_CNT(TIMER) = 0;
int tempi = adc_calc_tempi(temp_adc, vref_adc);
int tconvi = TIM_CNT(TIMER);
printf("ton: %u, tconv: %u, ch1: %u, ch5: %u\n", td, tconv, v1, v5);
printf("\tTemperature: %f (raw count: %u)\n", temp, temp_adc);
printf("\tTemperature: %f (tc %d) or %d (tc %d) (raw ts: %d, raw vref: %d)\n",
tempf, tconvf, tempi, tconvi, temp_adc, vref_adc);
//printf("\tT1-30 %d, t2-110 %d, vrefcal: %d\n", ST_TSENSE_CAL1_30C, ST_TSENSE_CAL2_110C, ST_VREFINT_CAL);
}
void adc_power_task_down()

6
tests/adc-power/main-stm32f4-disco.c
View file

@ -31,19 +31,19 @@ int main(void)
rcc_periph_clock_enable(RCC_GPIOA);
gpio_mode_setup(GPIOA, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, GPIO0);
gpio_mode_setup(GPIOA, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, GPIO1);
gpio_mode_setup(GPIOA, GPIO_MODE_ANALOG, GPIO_PUPD_NONE, GPIO5);
adc_power_init();
while (1) {
adc_power_task_up();
gpio_toggle(LED_DISCO_GREEN_PORT, LED_DISCO_GREEN_PIN);
for (i = 0; i < 0x1000000; i++) { /* Wait a bit. */
for (i = 0; i < 0x800000; i++) { /* Wait a bit. */
__asm__("NOP");
}
adc_power_task_down();
gpio_toggle(LED_DISCO_GREEN_PORT, LED_DISCO_GREEN_PIN);
for (i = 0; i < 0x1000000; i++) { /* Wait a bit. */
for (i = 0; i < 0x800000; i++) { /* Wait a bit. */
__asm__("NOP");
}
}