Tomo Yamanaka / mbed-dev

mbed library sources. Supersedes mbed-src. GR-PEACH runs on RAM.

Fork of mbed-dev by mbed official

targets/hal/TARGET_NXP/TARGET_LPC23XX/analogout_api.c@103:493a29d2d4d7, 2016-03-30 (annotated)

Committer:
1050186
Date:
Wed Mar 30 11:41:25 2016 +0000
Revision:
103:493a29d2d4d7
Parent:
0:9b334a45a8ff 
GR-PEACH runs on RAM.

Who changed what in which revision?

UserRevisionLine numberNew contents of line
bogdanm 0:9b334a45a8ff 1 /* mbed Microcontroller Library
bogdanm 0:9b334a45a8ff 2 * Copyright (c) 2006-2013 ARM Limited
bogdanm 0:9b334a45a8ff 3 *
bogdanm 0:9b334a45a8ff 4 * Licensed under the Apache License, Version 2.0 (the "License");
bogdanm 0:9b334a45a8ff 5 * you may not use this file except in compliance with the License.
bogdanm 0:9b334a45a8ff 6 * You may obtain a copy of the License at
bogdanm 0:9b334a45a8ff 7 *
bogdanm 0:9b334a45a8ff 8 * http://www.apache.org/licenses/LICENSE-2.0
bogdanm 0:9b334a45a8ff 9 *
bogdanm 0:9b334a45a8ff 10 * Unless required by applicable law or agreed to in writing, software
bogdanm 0:9b334a45a8ff 11 * distributed under the License is distributed on an "AS IS" BASIS,
bogdanm 0:9b334a45a8ff 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
bogdanm 0:9b334a45a8ff 13 * See the License for the specific language governing permissions and
bogdanm 0:9b334a45a8ff 14 * limitations under the License.
bogdanm 0:9b334a45a8ff 15 */
bogdanm 0:9b334a45a8ff 16 #include "mbed_assert.h"
bogdanm 0:9b334a45a8ff 17 #include "analogout_api.h"
bogdanm 0:9b334a45a8ff 18 #include "cmsis.h"
bogdanm 0:9b334a45a8ff 19 #include "pinmap.h"
bogdanm 0:9b334a45a8ff 20
bogdanm 0:9b334a45a8ff 21 static const PinMap PinMap_DAC[] = {
bogdanm 0:9b334a45a8ff 22 {P0_26, DAC_0, 2},
bogdanm 0:9b334a45a8ff 23 {NC , NC , 0}
bogdanm 0:9b334a45a8ff 24 };
bogdanm 0:9b334a45a8ff 25
bogdanm 0:9b334a45a8ff 26 void analogout_init(dac_t *obj, PinName pin) {
bogdanm 0:9b334a45a8ff 27 obj->dac = (DACName)pinmap_peripheral(pin, PinMap_DAC);
bogdanm 0:9b334a45a8ff 28 MBED_ASSERT(obj->dac != (DACName)NC);
bogdanm 0:9b334a45a8ff 29
bogdanm 0:9b334a45a8ff 30 // power is on by default, set DAC clk divider is /4
bogdanm 0:9b334a45a8ff 31 LPC_SC->PCLKSEL0 &= ~(0x3 << 22);
bogdanm 0:9b334a45a8ff 32
bogdanm 0:9b334a45a8ff 33 // map out (must be done before accessing registers)
bogdanm 0:9b334a45a8ff 34 pinmap_pinout(pin, PinMap_DAC);
bogdanm 0:9b334a45a8ff 35
bogdanm 0:9b334a45a8ff 36 analogout_write_u16(obj, 0);
bogdanm 0:9b334a45a8ff 37 }
bogdanm 0:9b334a45a8ff 38
bogdanm 0:9b334a45a8ff 39 void analogout_free(dac_t *obj) {}
bogdanm 0:9b334a45a8ff 40
bogdanm 0:9b334a45a8ff 41 static inline void dac_write(int value) {
bogdanm 0:9b334a45a8ff 42 value &= 0x3FF; // 10-bit
bogdanm 0:9b334a45a8ff 43
bogdanm 0:9b334a45a8ff 44 // Set the DAC output
bogdanm 0:9b334a45a8ff 45 LPC_DAC->DACR = (0 << 16) // bias = 0
bogdanm 0:9b334a45a8ff 46 | (value << 6);
bogdanm 0:9b334a45a8ff 47 }
bogdanm 0:9b334a45a8ff 48
bogdanm 0:9b334a45a8ff 49 static inline int dac_read() {
bogdanm 0:9b334a45a8ff 50 return (LPC_DAC->DACR >> 6) & 0x3FF;
bogdanm 0:9b334a45a8ff 51 }
bogdanm 0:9b334a45a8ff 52
bogdanm 0:9b334a45a8ff 53 void analogout_write(dac_t *obj, float value) {
bogdanm 0:9b334a45a8ff 54 if (value < 0.0f) {
bogdanm 0:9b334a45a8ff 55 dac_write(0);
bogdanm 0:9b334a45a8ff 56 } else if (value > 1.0f) {
bogdanm 0:9b334a45a8ff 57 dac_write(0x3FF);
bogdanm 0:9b334a45a8ff 58 } else {
bogdanm 0:9b334a45a8ff 59 dac_write(value * (float)0x3FF);
bogdanm 0:9b334a45a8ff 60 }
bogdanm 0:9b334a45a8ff 61 }
bogdanm 0:9b334a45a8ff 62
bogdanm 0:9b334a45a8ff 63 void analogout_write_u16(dac_t *obj, uint16_t value) {
bogdanm 0:9b334a45a8ff 64 dac_write(value >> 6); // 10-bit
bogdanm 0:9b334a45a8ff 65 }
bogdanm 0:9b334a45a8ff 66
bogdanm 0:9b334a45a8ff 67 float analogout_read(dac_t *obj) {
bogdanm 0:9b334a45a8ff 68 uint32_t value = dac_read();
bogdanm 0:9b334a45a8ff 69 return (float)value * (1.0f / (float)0x3FF);
bogdanm 0:9b334a45a8ff 70 }
bogdanm 0:9b334a45a8ff 71
bogdanm 0:9b334a45a8ff 72 uint16_t analogout_read_u16(dac_t *obj) {
bogdanm 0:9b334a45a8ff 73 uint32_t value = dac_read(); // 10-bit
bogdanm 0:9b334a45a8ff 74 return (value << 6) | ((value >> 4) & 0x003F);
bogdanm 0:9b334a45a8ff 75 }