Diff: mbed-dev/targets/TARGET_NXP/TARGET_LPC15XX/analogout_api.c

Revision:

18:6a4db94011d3

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mbed-dev/targets/TARGET_NXP/TARGET_LPC15XX/analogout_api.c	Sun May 14 23:18:57 2017 +0000
@@ -0,0 +1,71 @@
+/* mbed Microcontroller Library
+ * Copyright (c) 2006-2013 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"
+#include "cmsis.h"
+#include "pinmap.h"
+
+void analogout_init(dac_t *obj, PinName pin) {
+    MBED_ASSERT(pin == P0_12);
+    
+    LPC_SYSCON->SYSAHBCLKCTRL0 |= (1 << 29);
+    LPC_SYSCON->PDRUNCFG &= ~(1 << 12);
+    LPC_IOCON->PIO0_12 = 0;
+    LPC_SWM->PINENABLE0 &= ~(1 << 24);
+    LPC_DAC->CTRL = 0;
+    
+    analogout_write_u16(obj, 0);
+}
+
+void analogout_free(dac_t *obj)
+{
+    LPC_SYSCON->SYSAHBCLKCTRL0 &= ~(1 << 29);
+    LPC_SWM->PINENABLE0 |= (1 << 24);
+}
+
+static inline void dac_write(int value) {
+    value &= 0xFFF; // 12-bit
+    
+    // Set the DAC output
+    LPC_DAC->VAL = (value << 4);
+}
+
+static inline int dac_read() {
+    return ((LPC_DAC->VAL >> 4) & 0xFFF);
+}
+
+void analogout_write(dac_t *obj, float value) {
+    if (value < 0.0f) {
+        dac_write(0);
+    } else if (value > 1.0f) {
+        dac_write(0xFFF);
+    } else {
+        dac_write((uint32_t)(value * (float)0xFFF));
+    }
+}
+
+void analogout_write_u16(dac_t *obj, uint16_t value) {
+    dac_write(value);
+}
+
+float analogout_read(dac_t *obj) {
+    uint32_t value = dac_read();
+    return (float)value * (1.0f / (float)0xFFF);
+}
+
+uint16_t analogout_read_u16(dac_t *obj) {
+    return (uint16_t)dac_read();
+}