Diff: targets/TARGET_Freescale/TARGET_K20XX/analogout_api.c

Revision:

0:b74591d5ab33

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/targets/TARGET_Freescale/TARGET_K20XX/analogout_api.c	Mon Dec 11 17:54:04 2017 +0000
@@ -0,0 +1,84 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2015 ARM Limited
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+ 
+#include "mbed_assert.h"
+#include "analogout_api.h"
+
+#if DEVICE_ANALOGOUT
+
+#include "cmsis.h"
+#include "pinmap.h"
+#include "PeripheralPins.h"
+
+#define RANGE_12BIT     0xFFF
+
+void analogout_init(dac_t *obj, PinName pin) {
+    obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
+    MBED_ASSERT(obj->dac != (DACName)NC);
+
+    SIM->SCGC2 |= SIM_SCGC2_DAC0_MASK;
+
+    uint32_t port = (uint32_t)pin >> PORT_SHIFT;
+    SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port);
+
+    DAC0->DAT[obj->dac].DATH = 0;
+    DAC0->DAT[obj->dac].DATL = 0;
+
+    DAC0->C1 = DAC_C1_DACBFMD_MASK;     // One-Time Scan Mode
+
+    DAC0->C0 = DAC_C0_DACEN_MASK      // Enable
+             | DAC_C0_DACSWTRG_MASK   // Software Trigger
+             | DAC_C0_DACRFS_MASK;    // VDDA selected
+
+    analogout_write_u16(obj, 0);
+}
+
+void analogout_free(dac_t *obj) {}
+
+static inline void dac_write(dac_t *obj, int value) {
+    DAC0->DAT[obj->dac].DATL = (uint8_t)( value       & 0xFF);
+    DAC0->DAT[obj->dac].DATH = (uint8_t)((value >> 8) & 0xFF);
+}
+
+static inline int dac_read(dac_t *obj) {
+    return ((DAC0->DAT[obj->dac].DATH << 8) | DAC0->DAT[obj->dac].DATL);
+}
+
+void analogout_write(dac_t *obj, float value) {
+    if (value < 0.0) {
+        dac_write(obj, 0);
+    } else if (value > 1.0) {
+        dac_write(obj, RANGE_12BIT);
+    } else {
+        dac_write(obj, value * (float)RANGE_12BIT);
+    }
+}
+
+void analogout_write_u16(dac_t *obj, uint16_t value) {
+    dac_write(obj, value >> 4); // 12-bit
+}
+
+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) {
+    uint32_t value = dac_read(obj); // 12-bit
+    return (value << 4) | ((value >> 8) & 0x003F);
+}
+
+#endif