stm: Improve DAC (audio) bindings.

stm/audio.c

@@ -45,13 +45,26 @@ void audio_drain(void) {
     }
 }
 
+/******************************************************************************/
+// Micro Python bindings
+
+typedef struct _pyb_audio_t {
+    mp_obj_base_t base;
+    int dac_id; // 1 or 2
+} pyb_audio_t;
+
 // direct access to DAC
-mp_obj_t pyb_audio_dac(mp_obj_t val) {
+mp_obj_t pyb_audio_dac(mp_obj_t self_in, mp_obj_t val) {
-    DAC_SetChannel2Data(DAC_Align_8b_R, mp_obj_get_int(val));
+    pyb_audio_t *self = self_in;
+    if (self->dac_id == 1) {
+        DAC_SetChannel1Data(DAC_Align_8b_R, mp_obj_get_int(val));
+    } else {
+        DAC_SetChannel2Data(DAC_Align_8b_R, mp_obj_get_int(val));
+    }
     return mp_const_none;
 }
 
-mp_obj_t pyb_audio_is_full(void) {
+mp_obj_t pyb_audio_is_full(mp_obj_t self_in) {
     if (audio_is_full()) {
         return mp_const_true;
     } else {
@@ -59,42 +72,77 @@ mp_obj_t pyb_audio_is_full(void) {
     }
 }
 
-mp_obj_t pyb_audio_fill(mp_obj_t val) {
+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;
 }
 
-void audio_init(void) {
+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 const mp_method_t pyb_audio_methods[] = {
+    { "dac", &pyb_audio_dac_obj },
+    { "is_full", &pyb_audio_is_full_obj },
+    { "fill", &pyb_audio_fill_obj },
+    { NULL, NULL },
+};
+
+STATIC const mp_obj_type_t pyb_audio_type = {
+    { &mp_type_type },
+    .name = MP_QSTR_,
+    .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};
+
+// create the audio object
+// currently support either DAC1 on X5 (id = 1) or DAC2 on X6 (id = 2)
+
+STATIC mp_obj_t pyb_Audio(mp_obj_t id) {
     // DAC peripheral clock
     RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
 
-    // DAC channel 2 (DAC_OUT2 = PA.5) configuration
+    int dac_id = mp_obj_get_int(id);
+    uint pin;
+    uint channel;
+    mp_obj_t dac_obj;
+
+    if (dac_id == 1) {
+        pin = GPIO_Pin_4;
+        channel = DAC_Channel_1;
+        dac_obj = (mp_obj_t)&pyb_audio_channel_1;
+    } else {
+        pin = GPIO_Pin_5;
+        channel = DAC_Channel_2;
+        dac_obj = (mp_obj_t)&pyb_audio_channel_2;
+    }
+
+    // DAC channel configuration
     GPIO_InitTypeDef GPIO_InitStructure;
-    GPIO_InitStructure.GPIO_Pin = GPIO_Pin_5;
+    GPIO_InitStructure.GPIO_Pin = pin;
     GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
     GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL;
     GPIO_Init(GPIOA, &GPIO_InitStructure);
 
-    // DAC channel2 Configuration
+    // DAC channel Configuration
     DAC_InitTypeDef DAC_InitStructure;
     DAC_InitStructure.DAC_Trigger = DAC_Trigger_None;
     DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
     DAC_InitStructure.DAC_OutputBuffer = DAC_OutputBuffer_Enable;
-    DAC_Init(DAC_Channel_2, &DAC_InitStructure);
+    DAC_Init(channel, &DAC_InitStructure);
 
-    // Enable DAC Channel2
+    // Enable DAC Channel
-    DAC_Cmd(DAC_Channel_2, ENABLE);
+    DAC_Cmd(channel, ENABLE);
 
-    // from now on use DAC_SetChannel2Data to trigger a conversion
+    // from now on use DAC_SetChannel[12]Data to trigger a conversion
 
     sample_buf_in = 0;
     sample_buf_out = 0;
-    // enable interrupt
 
-    // Python interface
+    // return static object
-    mp_obj_t m = mp_obj_new_module(QSTR_FROM_STR_STATIC("audio"));
+    return dac_obj;
-    rt_store_attr(m, QSTR_FROM_STR_STATIC("dac"), rt_make_function_n(1, pyb_audio_dac));
-    rt_store_attr(m, QSTR_FROM_STR_STATIC("is_full"), rt_make_function_n(0, pyb_audio_is_full));
-    rt_store_attr(m, QSTR_FROM_STR_STATIC("fill"), rt_make_function_n(1, pyb_audio_fill));
-    rt_store_name(QSTR_FROM_STR_STATIC("audio"), m);
 }
+
+MP_DEFINE_CONST_FUN_OBJ_1(pyb_Audio_obj, pyb_Audio);

stm/audio.h

@@ -1 +1 @@
-void audio_init(void);
+MP_DECLARE_CONST_FUN_OBJ(pyb_Audio_obj);

stm/boards/PYBOARD4/mpconfigboard.h

@@ -12,7 +12,7 @@
 #define MICROPY_HW_ENABLE_RTC       (1)
 #define MICROPY_HW_ENABLE_TIMER     (1)
 #define MICROPY_HW_ENABLE_SERVO     (1)
-#define MICROPY_HW_ENABLE_AUDIO     (0)
+#define MICROPY_HW_ENABLE_AUDIO     (1)
 
 // USRSW has no pullup or pulldown, and pressing the switch makes the input go low
 #define USRSW_PIN           (pin_B3)

stm/main.c

@@ -387,11 +387,6 @@ soft_reset:
     servo_init();
 #endif
 
-#if MICROPY_HW_ENABLE_AUDIO
-    // audio
-    audio_init();
-#endif
-
 #if MICROPY_HW_ENABLE_TIMER
     // timer
     timer_init();
@@ -450,6 +445,10 @@ soft_reset:
         rt_store_attr(m, MP_QSTR_ADC, (mp_obj_t)&pyb_ADC_obj);
         rt_store_attr(m, qstr_from_str("millis"), rt_make_function_n(0, pyb_millis));
 
+#if MICROPY_HW_ENABLE_AUDIO
+        rt_store_attr(m, qstr_from_str("Audio"), (mp_obj_t)&pyb_Audio_obj);
+#endif
+
         pin_map_init(m);
         gpio_init(m);
         exti_init(m);