circuitpython/stmhal/dac.c

278 lines
9.2 KiB
C

#include <stdint.h>
#include <string.h>
#include "stm32f4xx_hal.h"
#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "parse.h"
#include "obj.h"
#include "runtime.h"
#include "dac.h"
TIM_HandleTypeDef TIM6_Handle;
STATIC DAC_HandleTypeDef DAC_Handle;
void dac_init(void) {
DAC_Handle.Instance = DAC;
DAC_Handle.State = HAL_DAC_STATE_RESET;
HAL_DAC_Init(&DAC_Handle);
}
STATIC void TIM6_Config(uint freq) {
// TIM6 clock enable
__TIM6_CLK_ENABLE();
// Compute the prescaler value so TIM6 triggers at freq-Hz
uint16_t period = (uint16_t) ((SystemCoreClock / 2) / freq) - 1;
// time base clock configuration
TIM6_Handle.Instance = TIM6;
TIM6_Handle.Init.Period = period;
TIM6_Handle.Init.Prescaler = 0; // timer runs at SystemCoreClock / 2
TIM6_Handle.Init.ClockDivision = 0; // unused for TIM6
TIM6_Handle.Init.CounterMode = TIM_COUNTERMODE_UP; // unused for TIM6
HAL_TIM_Base_Init(&TIM6_Handle);
// TIM6 TRGO selection
TIM_MasterConfigTypeDef config;
config.MasterOutputTrigger = TIM_TRGO_UPDATE;
config.MasterSlaveMode = TIM_MASTERSLAVEMODE_DISABLE;
HAL_TIMEx_MasterConfigSynchronization(&TIM6_Handle, &config);
// TIM6 start counter
HAL_TIM_Base_Start(&TIM6_Handle);
}
/******************************************************************************/
// Micro Python bindings
typedef struct _pyb_dac_obj_t {
mp_obj_base_t base;
uint32_t dac_channel; // DAC_CHANNEL_1 or DAC_CHANNEL_2
DMA_Stream_TypeDef *dma_stream; // DMA1_Stream5 or DMA1_Stream6
machine_uint_t state;
} pyb_dac_obj_t;
STATIC pyb_dac_obj_t pyb_dac_channel_1 = {{&pyb_dac_type}, DAC_CHANNEL_1, DMA1_Stream5};
STATIC pyb_dac_obj_t pyb_dac_channel_2 = {{&pyb_dac_type}, DAC_CHANNEL_2, DMA1_Stream6};
// create the dac object
// currently support either DAC1 on X5 (id = 1) or DAC2 on X6 (id = 2)
STATIC mp_obj_t pyb_dac_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
// check arguments
mp_check_nargs(n_args, 1, 1, n_kw, false);
machine_int_t dac_id = mp_obj_get_int(args[0]);
uint32_t pin;
pyb_dac_obj_t *dac_obj;
if (dac_id == 1) {
pin = GPIO_PIN_4;
dac_obj = &pyb_dac_channel_1;
} else if (dac_id == 2) {
pin = GPIO_PIN_5;
dac_obj = &pyb_dac_channel_2;
} else {
nlr_jump(mp_obj_new_exception_msg_varg(&mp_type_ValueError, "Dac %d does not exist", dac_id));
}
// GPIO configuration
GPIO_InitTypeDef GPIO_InitStructure;
GPIO_InitStructure.Pin = pin;
GPIO_InitStructure.Mode = GPIO_MODE_ANALOG;
GPIO_InitStructure.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStructure);
// DAC peripheral clock
__DAC_CLK_ENABLE();
// stop anything already going on
HAL_DAC_Stop(&DAC_Handle, dac_obj->dac_channel);
HAL_DAC_Stop_DMA(&DAC_Handle, dac_obj->dac_channel);
dac_obj->state = 0;
// return object
return dac_obj;
}
STATIC mp_obj_t pyb_dac_noise(mp_obj_t self_in, mp_obj_t freq) {
pyb_dac_obj_t *self = self_in;
// set TIM6 to trigger the DAC at the given frequency
TIM6_Config(mp_obj_get_int(freq));
if (self->state != 2) {
// configure DAC to trigger via TIM6
DAC_ChannelConfTypeDef config;
config.DAC_Trigger = DAC_TRIGGER_T6_TRGO;
config.DAC_OutputBuffer = DAC_OUTPUTBUFFER_ENABLE;
HAL_DAC_ConfigChannel(&DAC_Handle, &config, self->dac_channel);
self->state = 2;
}
// set noise wave generation
HAL_DACEx_NoiseWaveGenerate(&DAC_Handle, self->dac_channel, DAC_LFSRUNMASK_BITS10_0);
HAL_DAC_SetValue(&DAC_Handle, self->dac_channel, DAC_ALIGN_12B_L, 0x7ff0);
HAL_DAC_Start(&DAC_Handle, self->dac_channel);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_dac_noise_obj, pyb_dac_noise);
STATIC mp_obj_t pyb_dac_triangle(mp_obj_t self_in, mp_obj_t freq) {
pyb_dac_obj_t *self = self_in;
// set TIM6 to trigger the DAC at the given frequency
TIM6_Config(mp_obj_get_int(freq));
if (self->state != 2) {
// configure DAC to trigger via TIM6
DAC_ChannelConfTypeDef config;
config.DAC_Trigger = DAC_TRIGGER_T6_TRGO;
config.DAC_OutputBuffer = DAC_OUTPUTBUFFER_ENABLE;
HAL_DAC_ConfigChannel(&DAC_Handle, &config, self->dac_channel);
self->state = 2;
}
// set triangle wave generation
HAL_DACEx_TriangleWaveGenerate(&DAC_Handle, self->dac_channel, DAC_TRIANGLEAMPLITUDE_1023);
HAL_DAC_SetValue(&DAC_Handle, self->dac_channel, DAC_ALIGN_12B_R, 0x100);
HAL_DAC_Start(&DAC_Handle, self->dac_channel);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_dac_triangle_obj, pyb_dac_triangle);
// direct access to DAC (8 bit only at the moment)
STATIC mp_obj_t pyb_dac_write(mp_obj_t self_in, mp_obj_t val) {
pyb_dac_obj_t *self = self_in;
if (self->state != 1) {
DAC_ChannelConfTypeDef config;
config.DAC_Trigger = DAC_TRIGGER_NONE;
config.DAC_OutputBuffer = DAC_OUTPUTBUFFER_DISABLE;
HAL_DAC_ConfigChannel(&DAC_Handle, &config, self->dac_channel);
self->state = 1;
}
HAL_DAC_SetValue(&DAC_Handle, self->dac_channel, DAC_ALIGN_8B_R, mp_obj_get_int(val));
HAL_DAC_Start(&DAC_Handle, self->dac_channel);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_dac_write_obj, pyb_dac_write);
// initiates a burst of RAM->DAC using DMA
// input data is treated as an array of bytes (8 bit data)
// TIM6 is used to set the frequency of the transfer
// TODO still needs some attention to get it working properly
mp_obj_t pyb_dac_dma(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) {
pyb_dac_obj_t *self = args[0];
// set TIM6 to trigger the DAC at the given frequency
TIM6_Config(mp_obj_get_int(args[2]));
mp_obj_type_t *type = mp_obj_get_type(args[1]);
if (type->buffer_p.get_buffer == NULL) {
nlr_jump(mp_obj_new_exception_msg(&mp_type_TypeError, "buffer argument must support buffer protocol"));
}
buffer_info_t bufinfo;
type->buffer_p.get_buffer(args[1], &bufinfo, BUFFER_READ);
__DMA1_CLK_ENABLE();
/*
DMA_Cmd(self->dma_stream, DISABLE);
while (DMA_GetCmdStatus(self->dma_stream) != DISABLE) {
}
DAC_Cmd(self->dac_channel, DISABLE);
*/
/*
// DAC channel configuration
DAC_InitTypeDef DAC_InitStructure;
DAC_InitStructure.DAC_Trigger = DAC_Trigger_T7_TRGO;
DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_1; // unused, but need to set it to a valid value
DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
DAC_Init(self->dac_channel, &DAC_InitStructure);
*/
if (self->state != 3) {
DAC_ChannelConfTypeDef config;
config.DAC_Trigger = DAC_TRIGGER_T6_TRGO;
config.DAC_OutputBuffer = DAC_OUTPUTBUFFER_ENABLE;
HAL_DAC_ConfigChannel(&DAC_Handle, &config, self->dac_channel);
self->state = 3;
}
// DMA1_Stream[67] channel7 configuration
DMA_HandleTypeDef DMA_Handle;
DMA_Handle.Instance = self->dma_stream;
DMA_Handle.Init.Channel = DMA_CHANNEL_7;
DMA_Handle.Init.Direction = DMA_MEMORY_TO_PERIPH;
DMA_Handle.Init.PeriphInc = DMA_PINC_DISABLE;
DMA_Handle.Init.MemInc = DMA_MINC_ENABLE;
DMA_Handle.Init.PeriphDataAlignment = DMA_PDATAALIGN_BYTE;
DMA_Handle.Init.MemDataAlignment = DMA_MDATAALIGN_BYTE;
mp_map_elem_t *kw_mode = mp_map_lookup(kw_args, MP_OBJ_NEW_QSTR(qstr_from_str("mode")), MP_MAP_LOOKUP);
DMA_Handle.Init.Mode = kw_mode == NULL ? DMA_NORMAL : mp_obj_get_int(kw_mode->value); // normal = 0, circular = 0x100
DMA_Handle.Init.Priority = DMA_PRIORITY_HIGH;
DMA_Handle.Init.FIFOMode = DMA_FIFOMODE_DISABLE;
DMA_Handle.Init.FIFOThreshold = DMA_FIFO_THRESHOLD_HALFFULL;
DMA_Handle.Init.MemBurst = DMA_MBURST_SINGLE;
DMA_Handle.Init.PeriphBurst = DMA_PBURST_SINGLE;
HAL_DMA_Init(&DMA_Handle);
__HAL_LINKDMA(&DAC_Handle, DMA_Handle1, DMA_Handle);
HAL_DAC_Start_DMA(&DAC_Handle, self->dac_channel, (uint32_t*)bufinfo.buf, bufinfo.len, DAC_ALIGN_8B_R);
/*
// enable DMA stream
DMA_Cmd(self->dma_stream, ENABLE);
while (DMA_GetCmdStatus(self->dma_stream) == DISABLE) {
}
// enable DAC channel
DAC_Cmd(self->dac_channel, ENABLE);
// enable DMA for DAC channel
DAC_DMACmd(self->dac_channel, ENABLE);
*/
//printf("DMA: %p %lu\n", bufinfo.buf, bufinfo.len);
return mp_const_none;
}
STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_dac_dma_obj, 3, pyb_dac_dma);
STATIC const mp_map_elem_t pyb_dac_locals_dict_table[] = {
{ MP_OBJ_NEW_QSTR(MP_QSTR_noise), (mp_obj_t)&pyb_dac_noise_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_triangle), (mp_obj_t)&pyb_dac_triangle_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_write), (mp_obj_t)&pyb_dac_write_obj },
{ MP_OBJ_NEW_QSTR(MP_QSTR_dma), (mp_obj_t)&pyb_dac_dma_obj },
// TODO add function that does double buffering:
// dma2(freq, buf1, buf2, callback)
// where callback is called when the buffer has been drained
};
STATIC MP_DEFINE_CONST_DICT(pyb_dac_locals_dict, pyb_dac_locals_dict_table);
const mp_obj_type_t pyb_dac_type = {
{ &mp_type_type },
.name = MP_QSTR_DAC,
.make_new = pyb_dac_make_new,
.locals_dict = (mp_obj_t)&pyb_dac_locals_dict,
};