diff options
| -rw-r--r-- | stm/audio.c | 214 |
1 files changed, 161 insertions, 53 deletions
diff --git a/stm/audio.c b/stm/audio.c index 343ff7c19..77337282a 100644 --- a/stm/audio.c +++ b/stm/audio.c @@ -1,8 +1,6 @@ #include <stdint.h> #include <string.h> -#include "stm32f4xx_rcc.h" -#include "stm32f4xx_gpio.h" #include "stm32f4xx_dac.h" #include "nlr.h" @@ -11,38 +9,34 @@ #include "qstr.h" #include "parse.h" #include "obj.h" +#include "map.h" #include "runtime.h" #include "audio.h" -#define SAMPLE_BUF_SIZE (32) +STATIC void TIM7_Config(uint freq) { + // TIM7 clock enable + RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM7, ENABLE); -// sample_buf_in is always the same or ahead of sample_buf_out -// when they are the same, there are no more samples left to process -// in this scheme, there is always 1 unusable byte in the buffer, just before sample_buf_out -int sample_buf_in; -int sample_buf_out; -byte sample_buf[SAMPLE_BUF_SIZE]; + // reset TIM7 + TIM_DeInit(TIM7); -bool audio_is_full(void) { - return ((sample_buf_in + 1) % SAMPLE_BUF_SIZE) == sample_buf_out; -} + // Compute the prescaler value so TIM7 triggers at freq-Hz + uint16_t period = (uint16_t) ((SystemCoreClock / 2) / freq) - 1; -void audio_fill(byte sample) { - sample_buf[sample_buf_in] = sample; - sample_buf_in = (sample_buf_in + 1) % SAMPLE_BUF_SIZE; - // enable interrupt -} + // Time base configuration + TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure; + TIM_TimeBaseStructure.TIM_Period = period; // timer triggers with this period + TIM_TimeBaseStructure.TIM_Prescaler = 0; // timer runs at SystemCoreClock / 2 + TIM_TimeBaseStructure.TIM_ClockDivision = 0; // unused for TIM7 + TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up; // unused for TIM7 + TIM_TimeBaseInit(TIM7, &TIM_TimeBaseStructure); -void audio_drain(void) { - if (sample_buf_in == sample_buf_out) { - // buffer is empty; disable interrupt - } else { - // buffer has a sample; output it - byte sample = sample_buf[sample_buf_out]; - DAC_SetChannel2Data(DAC_Align_8b_R, sample); - sample_buf_out = (sample_buf_out + 1) % SAMPLE_BUF_SIZE; - } + // TIM7 TRGO selection + TIM_SelectOutputTrigger(TIM7, TIM_TRGOSource_Update); + + // TIM7 enable counter + TIM_Cmd(TIM7, ENABLE); } /******************************************************************************/ @@ -50,13 +44,67 @@ void audio_drain(void) { typedef struct _pyb_audio_t { mp_obj_base_t base; - int dac_id; // 1 or 2 + uint dac_channel; // DAC_Channel_1 or DAC_Channel_2 + DMA_Stream_TypeDef *dma_stream; // DMA1_Stream6 or DMA1_Stream7 } pyb_audio_t; +mp_obj_t pyb_audio_noise(mp_obj_t self_in, mp_obj_t freq) { + pyb_audio_t *self = self_in; + + // set TIM7 to trigger the DAC at the given frequency + TIM7_Config(mp_obj_get_int(freq)); + + DAC_Cmd(self->dac_channel, DISABLE); + + DAC_InitTypeDef DAC_InitStructure; + DAC_InitStructure.DAC_Trigger = DAC_Trigger_T7_TRGO; + DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_Noise; + DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_LFSRUnmask_Bits10_0; + DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable; + DAC_Init(self->dac_channel, &DAC_InitStructure); + + DAC_Cmd(self->dac_channel, ENABLE); + + if (self->dac_channel == DAC_Channel_1) { + DAC_SetChannel1Data(DAC_Align_12b_L, 0x7ff0); + } else { + DAC_SetChannel2Data(DAC_Align_12b_L, 0x7ff0); + } + + return mp_const_none; +} + +mp_obj_t pyb_audio_triangle(mp_obj_t self_in, mp_obj_t freq) { + pyb_audio_t *self = self_in; + + // set TIM7 to trigger the DAC at the given frequency + TIM7_Config(mp_obj_get_int(freq)); + + DAC_Cmd(self->dac_channel, DISABLE); + + DAC_InitTypeDef DAC_InitStructure; + DAC_InitStructure.DAC_Trigger = DAC_Trigger_T7_TRGO; + DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_Triangle; + DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_1023; + DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable; + DAC_Init(self->dac_channel, &DAC_InitStructure); + + DAC_Cmd(self->dac_channel, ENABLE); + + // set base value of triangle wave + if (self->dac_channel == DAC_Channel_1) { + DAC_SetChannel1Data(DAC_Align_12b_R, 0x100); + } else { + DAC_SetChannel2Data(DAC_Align_12b_R, 0x100); + } + + return mp_const_none; +} + // direct access to DAC mp_obj_t pyb_audio_dac(mp_obj_t self_in, mp_obj_t val) { pyb_audio_t *self = self_in; - if (self->dac_id == 1) { + if (self->dac_channel == DAC_Channel_1) { DAC_SetChannel1Data(DAC_Align_8b_R, mp_obj_get_int(val)); } else { DAC_SetChannel2Data(DAC_Align_8b_R, mp_obj_get_int(val)); @@ -64,27 +112,92 @@ mp_obj_t pyb_audio_dac(mp_obj_t self_in, mp_obj_t val) { return mp_const_none; } -mp_obj_t pyb_audio_is_full(mp_obj_t self_in) { - if (audio_is_full()) { - return mp_const_true; +#define DAC_DHR8R1_ADDRESS (DAC_BASE + 0x10) +#define DAC_DHR8R2_ADDRESS (DAC_BASE + 0x1c) + +// initiates a burst of RAM->DAC using DMA +// input data is treated as an array of bytes (8 bit data) +// TIM7 is used to set the frequency of the transfer +mp_obj_t pyb_audio_dma(uint n_args, const mp_obj_t *args, mp_map_t *kw_args) { + pyb_audio_t *self = args[0]; + + // set TIM7 to trigger the DAC at the given frequency + TIM7_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); + + RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_DMA1, 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); + + // DMA1_Stream[67] channel7 configuration + DMA_DeInit(self->dma_stream); + DMA_InitTypeDef DMA_InitStructure; + DMA_InitStructure.DMA_Channel = DMA_Channel_7; + if (self->dac_channel == DAC_Channel_1) { + DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR8R1_ADDRESS; } else { - return mp_const_false; + DMA_InitStructure.DMA_PeripheralBaseAddr = DAC_DHR8R2_ADDRESS; } -} + DMA_InitStructure.DMA_Memory0BaseAddr = (uint32_t)bufinfo.buf; + DMA_InitStructure.DMA_DIR = DMA_DIR_MemoryToPeripheral; + DMA_InitStructure.DMA_BufferSize = bufinfo.len; + DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable; + DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; + DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Byte; + DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Byte; + mp_map_elem_t *kw_mode = mp_map_lookup(kw_args, MP_OBJ_NEW_QSTR(qstr_from_str("mode")), MP_MAP_LOOKUP); + DMA_InitStructure.DMA_Mode = kw_mode == NULL ? DMA_Mode_Normal : mp_obj_get_int(kw_mode->value); // normal = 0, circular = 0x100 + DMA_InitStructure.DMA_Priority = DMA_Priority_High; + DMA_InitStructure.DMA_FIFOMode = DMA_FIFOMode_Disable; + DMA_InitStructure.DMA_FIFOThreshold = DMA_FIFOThreshold_HalfFull; + DMA_InitStructure.DMA_MemoryBurst = DMA_MemoryBurst_Single; + DMA_InitStructure.DMA_PeripheralBurst = DMA_PeripheralBurst_Single; + DMA_Init(self->dma_stream, &DMA_InitStructure); + + // 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); -mp_obj_t pyb_audio_fill(mp_obj_t self_in, mp_obj_t val) { - audio_fill(mp_obj_get_int(val)); return mp_const_none; } +STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_audio_noise_obj, pyb_audio_noise); +STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_audio_triangle_obj, pyb_audio_triangle); STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_audio_dac_obj, pyb_audio_dac); -STATIC MP_DEFINE_CONST_FUN_OBJ_1(pyb_audio_is_full_obj, pyb_audio_is_full); -STATIC MP_DEFINE_CONST_FUN_OBJ_2(pyb_audio_fill_obj, pyb_audio_fill); +STATIC MP_DEFINE_CONST_FUN_OBJ_KW(pyb_audio_dma_obj, 3, pyb_audio_dma); STATIC const mp_method_t pyb_audio_methods[] = { + { "noise", &pyb_audio_noise_obj }, + { "triangle", &pyb_audio_triangle_obj }, { "dac", &pyb_audio_dac_obj }, - { "is_full", &pyb_audio_is_full_obj }, - { "fill", &pyb_audio_fill_obj }, + { "dma", &pyb_audio_dma_obj }, { NULL, NULL }, }; @@ -94,8 +207,8 @@ STATIC const mp_obj_type_t pyb_audio_type = { .methods = pyb_audio_methods, }; -STATIC const pyb_audio_t pyb_audio_channel_1 = {{&pyb_audio_type}, 1}; -STATIC const pyb_audio_t pyb_audio_channel_2 = {{&pyb_audio_type}, 2}; +STATIC const pyb_audio_t pyb_audio_channel_1 = {{&pyb_audio_type}, DAC_Channel_1, DMA1_Stream5}; +STATIC const pyb_audio_t pyb_audio_channel_2 = {{&pyb_audio_type}, DAC_Channel_2, DMA1_Stream6}; // create the audio object // currently support either DAC1 on X5 (id = 1) or DAC2 on X6 (id = 2) @@ -106,17 +219,14 @@ STATIC mp_obj_t pyb_Audio(mp_obj_t id) { int dac_id = mp_obj_get_int(id); uint pin; - uint channel; - mp_obj_t dac_obj; + const pyb_audio_t *dac_obj; if (dac_id == 1) { pin = GPIO_Pin_4; - channel = DAC_Channel_1; - dac_obj = (mp_obj_t)&pyb_audio_channel_1; + dac_obj = &pyb_audio_channel_1; } else { pin = GPIO_Pin_5; - channel = DAC_Channel_2; - dac_obj = (mp_obj_t)&pyb_audio_channel_2; + dac_obj = &pyb_audio_channel_2; } // DAC channel configuration @@ -130,19 +240,17 @@ STATIC mp_obj_t pyb_Audio(mp_obj_t id) { DAC_InitTypeDef DAC_InitStructure; DAC_InitStructure.DAC_Trigger = DAC_Trigger_None; DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None; + DAC_InitStructure.DAC_LFSRUnmask_TriangleAmplitude = DAC_TriangleAmplitude_1023; DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable; - DAC_Init(channel, &DAC_InitStructure); + DAC_Init(dac_obj->dac_channel, &DAC_InitStructure); // Enable DAC Channel - DAC_Cmd(channel, ENABLE); + DAC_Cmd(dac_obj->dac_channel, ENABLE); // from now on use DAC_SetChannel[12]Data to trigger a conversion - sample_buf_in = 0; - sample_buf_out = 0; - // return static object - return dac_obj; + return (mp_obj_t)dac_obj; } MP_DEFINE_CONST_FUN_OBJ_1(pyb_Audio_obj, pyb_Audio); |