Diff: targets/hal/TARGET_STM/TARGET_STM32L4/analogout_api.c

Revision:

8:69ce7aaad4c4

Parent:

0:9b334a45a8ff

--- a/targets/hal/TARGET_STM/TARGET_STM32L4/analogout_api.c	Fri Oct 16 07:45:35 2015 +0100
+++ b/targets/hal/TARGET_STM/TARGET_STM32L4/analogout_api.c	Mon Oct 26 09:00:10 2015 +0000
@@ -36,6 +36,7 @@
 #include "PeripheralPins.h"
 
 #define DAC_RANGE (0xFFF) // 12 bits
+#define DAC_NB_BITS  (12)
 
 static DAC_HandleTypeDef DacHandle;
 
@@ -43,8 +44,7 @@
 static int channel1_used = 0;
 static int channel2_used = 0;
 
-void analogout_init(dac_t *obj, PinName pin)
-{
+void analogout_init(dac_t *obj, PinName pin) {
     DAC_ChannelConfTypeDef sConfig = {0};
 
     // Get the peripheral name from the pin and assign it to the object
@@ -94,8 +94,7 @@
     analogout_write_u16(obj, 0);
 }
 
-void analogout_free(dac_t *obj)
-{
+void analogout_free(dac_t *obj) {
     // Reset DAC and disable clock
     if (obj->channel == 1) channel1_used = 0;
     if (obj->channel == 2) channel2_used = 0;
@@ -110,20 +109,18 @@
     pin_function(obj->pin, STM_PIN_DATA(STM_MODE_INPUT, GPIO_NOPULL, 0));
 }
 
-static inline void dac_write(dac_t *obj, uint16_t value)
-{
+static inline void dac_write(dac_t *obj, int value) {
     if (obj->channel == 1) {
-        HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_1, DAC_ALIGN_12B_R, value);
+        HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_1, DAC_ALIGN_12B_R, (value & DAC_RANGE));
         HAL_DAC_Start(&DacHandle, DAC_CHANNEL_1);
     }
     if (obj->channel == 2) {
-        HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_2, DAC_ALIGN_12B_R, value);
+        HAL_DAC_SetValue(&DacHandle, DAC_CHANNEL_2, DAC_ALIGN_12B_R, (value & DAC_RANGE));
         HAL_DAC_Start(&DacHandle, DAC_CHANNEL_2);
     }
 }
 
-static inline int dac_read(dac_t *obj)
-{
+static inline int dac_read(dac_t *obj) {
     if (obj->channel == 1) {
         return (int)HAL_DAC_GetValue(&DacHandle, DAC_CHANNEL_1);
     }
@@ -133,35 +130,28 @@
     return 0;
 }
 
-void analogout_write(dac_t *obj, float value)
-{
+void analogout_write(dac_t *obj, float value) {
     if (value < 0.0f) {
         dac_write(obj, 0); // Min value
     } else if (value > 1.0f) {
-        dac_write(obj, (uint16_t)DAC_RANGE); // Max value
+        dac_write(obj, (int)DAC_RANGE); // Max value
     } else {
-        dac_write(obj, (uint16_t)(value * (float)DAC_RANGE));
+        dac_write(obj, (int)(value * (float)DAC_RANGE));
     }
 }
 
-void analogout_write_u16(dac_t *obj, uint16_t value)
-{
-    if (value > (uint16_t)DAC_RANGE) {
-        dac_write(obj, (uint16_t)DAC_RANGE); // Max value
-    } else {
-        dac_write(obj, value);
-    }
+void analogout_write_u16(dac_t *obj, uint16_t value) {
+    dac_write(obj, value >> (16 - DAC_NB_BITS));
 }
 
-float analogout_read(dac_t *obj)
-{
+float analogout_read(dac_t *obj) {
     uint32_t value = dac_read(obj);
-    return (float)((float)value * (1.0f / (float)DAC_RANGE));
+    return (float)value * (1.0f / (float)DAC_RANGE);
 }
 
-uint16_t analogout_read_u16(dac_t *obj)
-{
-    return (uint16_t)dac_read(obj);
+uint16_t analogout_read_u16(dac_t *obj) {
+    uint32_t value = dac_read(obj);
+    return (value << 4) | ((value >> 8) & 0x000F); // Conversion from 12 to 16 bits
 }
 
 #endif // DEVICE_ANALOGOUT