kopia lustrzana https://github.com/OpenRTX/OpenRTX
Refactoring of MDx ADC1 driver: removed DMA, added function allowing to retrieve the raw conversion value, changed return value of 'adc1_getMeasurement' from float to uint16_t (TG-276 #closed)
Silvano Seva
Federico Amedeo Izzo
rodzic
c69c2be478
commit
5dc2ba25d8
|
|
@ -17,36 +17,18 @@
|
|||
|
||||
#include <interfaces/gpio.h>
|
||||
#include <hwconfig.h>
|
||||
#include <pthread.h>
|
||||
#include <stdlib.h>
|
||||
#include "ADC1_MDx.h"
|
||||
|
||||
|
||||
/*
|
||||
* The sample buffer is structured as follows:
|
||||
*
|
||||
* | vol | vbat | vox | rssi | sw1 | sw2 | rssi2 | htemp |
|
||||
*
|
||||
* NOTE: we are forced to allocate it through a malloc in order to make it be
|
||||
* in the "large" 128kB RAM. This because the linker script maps the .data and
|
||||
* .bss sections in the "small" 64kB CCM RAM, which cannot be reached by the DMA.
|
||||
*/
|
||||
uint16_t *sampleBuf = NULL;
|
||||
|
||||
#if defined(PLATFORM_MD9600)
|
||||
static const size_t nChannels = 8;
|
||||
#elif defined(PLATFORM_MD3x0)
|
||||
static const size_t nChannels = 4;
|
||||
#else
|
||||
static const size_t nChannels = 2;
|
||||
#endif
|
||||
pthread_mutex_t adcMutex;
|
||||
|
||||
void adc1_init()
|
||||
{
|
||||
RCC->APB2ENR |= RCC_APB2ENR_ADC1EN;
|
||||
RCC->AHB1ENR |= RCC_AHB1ENR_DMA2EN;
|
||||
__DSB();
|
||||
pthread_mutex_init(&adcMutex, NULL);
|
||||
|
||||
sampleBuf = ((uint16_t *) malloc(4 * sizeof(uint16_t)));
|
||||
RCC->APB2ENR |= RCC_APB2ENR_ADC1EN;
|
||||
__DSB();
|
||||
|
||||
/*
|
||||
* Configure GPIOs to analog input mode:
|
||||
|
|
@ -66,91 +48,63 @@ void adc1_init()
|
|||
|
||||
/*
|
||||
* ADC clock is APB2 frequency divided by 8, giving 10.5MHz.
|
||||
* We set the sample time of each channel to 480 ADC cycles and we have to
|
||||
* scan four channels: given that a conversion takes 12 cycles, we have a
|
||||
* total conversion time of ~187us.
|
||||
* We set the sample time of each channel to 84 ADC cycles and we have that
|
||||
* a conversion takes 12 cycles: total conversion time is then of ~9us.
|
||||
*/
|
||||
ADC->CCR |= ADC_CCR_ADCPRE;
|
||||
ADC1->SMPR2 = ADC_SMPR2_SMP0
|
||||
| ADC_SMPR2_SMP1
|
||||
| ADC_SMPR2_SMP3
|
||||
| ADC_SMPR2_SMP6
|
||||
| ADC_SMPR2_SMP7
|
||||
| ADC_SMPR2_SMP8
|
||||
| ADC_SMPR2_SMP9;
|
||||
ADC1->SMPR1 = ADC_SMPR1_SMP15;
|
||||
ADC->CCR |= ADC_CCR_ADCPRE;
|
||||
ADC1->SMPR2 = ADC_SMPR2_SMP0_2
|
||||
| ADC_SMPR2_SMP1_2
|
||||
| ADC_SMPR2_SMP3_2
|
||||
| ADC_SMPR2_SMP6_2
|
||||
| ADC_SMPR2_SMP7_2
|
||||
| ADC_SMPR2_SMP8_2
|
||||
| ADC_SMPR2_SMP9_2;
|
||||
ADC1->SMPR1 = ADC_SMPR1_SMP15_2;
|
||||
|
||||
/*
|
||||
* No overrun interrupt, 12-bit resolution, no analog watchdog, no
|
||||
* discontinuous mode, enable scan mode, no end of conversion interrupts,
|
||||
* enable continuous conversion (free-running).
|
||||
* Convert one channel, no overrun interrupt, 12-bit resolution,
|
||||
* no analog watchdog, discontinuous mode, no end of conversion interrupts,
|
||||
* turn on ADC.
|
||||
*/
|
||||
ADC1->CR1 |= ADC_CR1_SCAN;
|
||||
ADC1->CR2 |= ADC_CR2_DMA
|
||||
| ADC_CR2_DDS
|
||||
| ADC_CR2_CONT
|
||||
| ADC_CR2_ADON;
|
||||
|
||||
/* Scan sequence config. */
|
||||
#if defined(PLATFORM_MD9600)
|
||||
ADC1->SQR1 = 7 << 20; /* Eight channels to be converted */
|
||||
ADC1->SQR3 |= (0 << 0) /* CH0, volume potentiometer level on PA0 */
|
||||
| (1 << 5) /* CH1, battery voltage on PA1 */
|
||||
| (3 << 10) /* CH3, vox level on PA3 */
|
||||
| (8 << 15) /* CH8, RSSI value on PB0 */
|
||||
| (7 << 20) /* CH7, SW1 value on PA7 */
|
||||
| (6 << 25); /* CH6, SW2 value on PA6 */
|
||||
ADC1->SQR2 |= (9 << 0) /* CH9, RSSI2 value on PB1 */
|
||||
| (15 << 5); /* CH15, HTEMP value on PC5 */
|
||||
#elif defined(PLATFORM_MD3x0)
|
||||
ADC1->SQR1 = 3 << 20; /* Four channels to be converted */
|
||||
ADC1->SQR3 |= (0 << 0) /* CH0, volume potentiometer level on PA0 */
|
||||
| (1 << 5) /* CH1, battery voltage on PA1 */
|
||||
| (3 << 10) /* CH3, vox level on PA3 */
|
||||
| (8 << 15); /* CH8, RSSI value on PB0 */
|
||||
#else
|
||||
ADC1->SQR1 = 1 << 20; /* Convert two channel */
|
||||
ADC1->SQR3 |= (0 << 0) /* CH0, volume potentiometer level on PA0 */
|
||||
| (1 << 5); /* CH1, battery voltage on PA1 */
|
||||
#endif
|
||||
|
||||
/* DMA2 Stream 0 configuration:
|
||||
* - channel 0: ADC1
|
||||
* - low priority
|
||||
* - half-word transfer, both memory and peripheral
|
||||
* - increment memory
|
||||
* - circular mode
|
||||
* - peripheral-to-memory transfer
|
||||
* - no interrupts
|
||||
*/
|
||||
DMA2_Stream0->PAR = ((uint32_t) &(ADC1->DR));
|
||||
DMA2_Stream0->M0AR = ((uint32_t) sampleBuf);
|
||||
DMA2_Stream0->NDTR = nChannels;
|
||||
DMA2_Stream0->CR = DMA_SxCR_MSIZE_0 /* Memory size: 16 bit */
|
||||
| DMA_SxCR_PSIZE_0 /* Peripheral size: 16 bit */
|
||||
| DMA_SxCR_PL_0 /* Medium priority */
|
||||
| DMA_SxCR_MINC /* Increment memory */
|
||||
| DMA_SxCR_CIRC /* Circular mode */
|
||||
| DMA_SxCR_EN;
|
||||
|
||||
/* Finally, start conversion */
|
||||
ADC1->CR2 |= ADC_CR2_SWSTART;
|
||||
ADC1->SQR1 = 0;
|
||||
ADC1->CR2 = ADC_CR2_ADON;
|
||||
}
|
||||
|
||||
void adc1_terminate()
|
||||
{
|
||||
free(sampleBuf);
|
||||
sampleBuf = NULL;
|
||||
DMA2_Stream0->CR &= ~DMA_SxCR_EN;
|
||||
ADC1->CR2 &= ~ADC_CR2_ADON;
|
||||
pthread_mutex_destroy(&adcMutex);
|
||||
|
||||
ADC1->CR2 &= ~ADC_CR2_ADON;
|
||||
RCC->APB2ENR &= ~RCC_APB2ENR_ADC1EN;
|
||||
__DSB();
|
||||
}
|
||||
|
||||
float adc1_getMeasurement(uint8_t ch)
|
||||
uint16_t adc1_getRawSample(uint8_t ch)
|
||||
{
|
||||
if((ch > (nChannels-1)) || (sampleBuf == NULL)) return 0.0f;
|
||||
if(ch > 15) return 0;
|
||||
|
||||
float value = ((float) sampleBuf[ch]);
|
||||
return (value * 3300.0f)/4096.0f;
|
||||
pthread_mutex_lock(&adcMutex);
|
||||
|
||||
ADC1->SQR3 = ch;
|
||||
ADC1->CR2 |= ADC_CR2_SWSTART;
|
||||
while((ADC1->SR & ADC_SR_EOC) == 0) ;
|
||||
uint16_t value = ADC1->DR;
|
||||
|
||||
pthread_mutex_unlock(&adcMutex);
|
||||
|
||||
return value;
|
||||
}
|
||||
|
||||
uint16_t adc1_getMeasurement(uint8_t ch)
|
||||
{
|
||||
/*
|
||||
* To avoid using floats, we convert the raw ADC sample to mV using 16.16
|
||||
* fixed point math. The equation for conversion is (sample * 3300)/4096 but,
|
||||
* since converting the raw ADC sample to 16.16 notation requires a left
|
||||
* shift by 16 and dividing by 4096 is equivalent to shifting right by 12,
|
||||
* we just shift left by four and then multiply by 3300.
|
||||
* With respect to using floats, maximum error is -1mV.
|
||||
*/
|
||||
uint32_t sample = (adc1_getRawSample(ch) << 4) * 3300;
|
||||
return ((uint16_t) (sample >> 16));
|
||||
}
|
||||
|
|
|
|||
|
|
@ -42,38 +42,43 @@ extern "C" {
|
|||
* | PB1 | IN9 | | | | x |
|
||||
* | PC5 | IN15 | heatsink temp. | | | x |
|
||||
* +-----+------+-----------------+--------+----------+---------+
|
||||
*
|
||||
* NOTE: values inside the enum are the channel numbers of STM32 ADC1 peripheral.
|
||||
*/
|
||||
|
||||
enum adcCh
|
||||
{
|
||||
ADC_VOL_CH = 0,
|
||||
ADC_VBAT_CH = 1,
|
||||
ADC_VOX_CH = 2,
|
||||
ADC_RSSI_CH = 3,
|
||||
ADC_SW1_CH = 4,
|
||||
ADC_SW2_CH = 5,
|
||||
ADC_RSSI2_CH = 6,
|
||||
ADC_HTEMP_CH = 7
|
||||
ADC_VOX_CH = 3,
|
||||
ADC_RSSI_CH = 8,
|
||||
ADC_SW1_CH = 7,
|
||||
ADC_SW2_CH = 6,
|
||||
ADC_RSSI2_CH = 9,
|
||||
ADC_HTEMP_CH = 15
|
||||
};
|
||||
|
||||
/**
|
||||
* Initialise and start ADC1 and DMA2 Stream 0.
|
||||
*
|
||||
* ADC is configured in free-running mode with 1:8 prescaler and a sample time
|
||||
* for each channel of 480 cycles. This gives a sampling frequency, for each
|
||||
* channel, of ~5.3kHz.
|
||||
*
|
||||
* DMA2 Stream 0 is used to transfer data from ADC1 data register to an internal
|
||||
* buffer, from which is fetched by application code using adc1_getMeasurement().
|
||||
* Initialise ADC1.
|
||||
*/
|
||||
void adc1_init();
|
||||
|
||||
/**
|
||||
* Turn off ADC1 (also gating off its clock) and disable DMA2 Stream 0.
|
||||
* DMA2 clock is kept active.
|
||||
* Turn off ADC1.
|
||||
*/
|
||||
void adc1_terminate();
|
||||
|
||||
/**
|
||||
* Get current measurement of a given channel returning the raw ADC value.
|
||||
*
|
||||
* NOTE: the mapping provided in enum adcCh DOES NOT correspond to the physical
|
||||
* ADC channel mapping!
|
||||
*
|
||||
* @param ch: channel number.
|
||||
* @return current value of the specified channel, in ADC counts.
|
||||
*/
|
||||
uint16_t adc1_getRawSample(uint8_t ch);
|
||||
|
||||
/**
|
||||
* Get current measurement of a given channel.
|
||||
*
|
||||
|
|
@ -83,7 +88,7 @@ void adc1_terminate();
|
|||
* @param ch: channel number.
|
||||
* @return current value of the specified channel in mV.
|
||||
*/
|
||||
float adc1_getMeasurement(uint8_t ch);
|
||||
uint16_t adc1_getMeasurement(uint8_t ch);
|
||||
|
||||
#ifdef __cplusplus
|
||||
}
|
||||
|
|
|
|||
Ładowanie…
Reference in New Issue