[NUCLEO_L152RE] Add analog out api

Author: bcostm

libraries/mbed/targets/hal/TARGET_STM/TARGET_NUCLEO_L152RE/analogout_api.c

@@ -0,0 +1,129 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2014, STMicroelectronics
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright notice,
+ *    this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright notice,
+ *    this list of conditions and the following disclaimer in the documentation
+ *    and/or other materials provided with the distribution.
+ * 3. Neither the name of STMicroelectronics nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+ * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+ * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "analogout_api.h"
+
+#if DEVICE_ANALOGOUT
+
+#include "cmsis.h"
+#include "pinmap.h"
+#include "error.h"
+
+#define RANGE_12BIT (0xFFF)
+
+static const PinMap PinMap_DAC[] = {
+    {PA_4, DAC_1, STM_PIN_DATA(GPIO_Mode_AN, GPIO_OType_PP, GPIO_PuPd_NOPULL, 0xFF)}, // DAC_OUT1
+    //{PA_5, DAC_1, STM_PIN_DATA(GPIO_Mode_AN, GPIO_OType_PP, GPIO_PuPd_NOPULL, 0xFF)}, // DAC_OUT2 - Cannot be used due to the LED connected on it
+    {NC,   NC,    0}
+};
+
+void analogout_init(dac_t *obj, PinName pin) {
+    DAC_InitTypeDef DAC_InitStructure;
+  
+    // Get the peripheral name (DAC_1, ...) from the pin and assign it to the object
+    obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
+
+    if (obj->dac == (DACName)NC) {
+        error("DAC pin mapping failed");
+    }
+
+    // Configure GPIO
+    pinmap_pinout(pin, PinMap_DAC);
+
+    // Save the channel for the write and read functions
+    obj->channel = pin;
+
+    // Enable DAC clock
+    RCC_APB1PeriphClockCmd(RCC_APB1Periph_DAC, ENABLE);
+
+    // Configure and enable DAC channel
+    DAC_InitStructure.DAC_Trigger        = DAC_Trigger_None;
+    DAC_InitStructure.DAC_WaveGeneration = DAC_WaveGeneration_None;
+    DAC_InitStructure.DAC_OutputBuffer   = DAC_OutputBuffer_Disable;
+    
+    if (pin == PA_4) {
+      DAC_Init(DAC_Channel_1, &DAC_InitStructure);
+      DAC_Cmd(DAC_Channel_1, ENABLE);
+    }
+    else { // PA_5
+      DAC_Init(DAC_Channel_2, &DAC_InitStructure);
+      DAC_Cmd(DAC_Channel_2, ENABLE);
+    }
+              
+    analogout_write_u16(obj, 0);
+}
+
+void analogout_free(dac_t *obj) {
+}
+
+static inline void dac_write(dac_t *obj, uint16_t value) {
+    if (obj->channel == PA_4) {
+      DAC_SetChannel1Data(DAC_Align_12b_R, value);
+    }
+    else { // PA_5
+      DAC_SetChannel2Data(DAC_Align_12b_R, value);
+    }
+}
+
+static inline int dac_read(dac_t *obj) {
+    if (obj->channel == PA_4) {
+      return (int)DAC_GetDataOutputValue(DAC_Channel_1);
+    }
+    else { // PA_5
+      return (int)DAC_GetDataOutputValue(DAC_Channel_2);
+    }
+}
+
+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)RANGE_12BIT); // Max value
+    } else {
+        dac_write(obj, (uint16_t)(value * (float)RANGE_12BIT));
+    }
+}
+
+void analogout_write_u16(dac_t *obj, uint16_t value) {
+    if (value > (uint16_t)RANGE_12BIT) {
+      dac_write(obj, (uint16_t)RANGE_12BIT); // Max value
+    }
+    else {
+      dac_write(obj, value);
+    }
+}
+
+float analogout_read(dac_t *obj) {
+    uint32_t value = dac_read(obj);
+    return (float)value * (1.0f / (float)RANGE_12BIT);
+}
+
+uint16_t analogout_read_u16(dac_t *obj) {
+    return (uint16_t)dac_read(obj);
+}
+
+#endif // DEVICE_ANALOGOUT