shao ziyang / mbed-src-kl05

mbed library sources

Dependents:   frdm_kl05z_gpio_test

Fork of mbed-src by mbed official

targets/hal/TARGET_Freescale/TARGET_K20D50M/analogin_api.c@255:20b371a9491b, 2014-07-11 (annotated)

Committer:
mbed_official
Date:
Fri Jul 11 10:00:08 2014 +0100
Revision:
255:20b371a9491b
Synchronized with git revision bbf5cbc71510e72033aaacbd76c3f127b70f08b6



Full URL: https://github.com/mbedmicro/mbed/commit/bbf5cbc71510e72033aaacbd76c3f127b70f08b6/



[K20D50M] K20D5M -> K20D50M

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 255:20b371a9491b 1 /* mbed Microcontroller Library
mbed_official 255:20b371a9491b 2 * Copyright (c) 2006-2013 ARM Limited
mbed_official 255:20b371a9491b 3 *
mbed_official 255:20b371a9491b 4 * Licensed under the Apache License, Version 2.0 (the "License");
mbed_official 255:20b371a9491b 5 * you may not use this file except in compliance with the License.
mbed_official 255:20b371a9491b 6 * You may obtain a copy of the License at
mbed_official 255:20b371a9491b 7 *
mbed_official 255:20b371a9491b 8 * http://www.apache.org/licenses/LICENSE-2.0
mbed_official 255:20b371a9491b 9 *
mbed_official 255:20b371a9491b 10 * Unless required by applicable law or agreed to in writing, software
mbed_official 255:20b371a9491b 11 * distributed under the License is distributed on an "AS IS" BASIS,
mbed_official 255:20b371a9491b 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
mbed_official 255:20b371a9491b 13 * See the License for the specific language governing permissions and
mbed_official 255:20b371a9491b 14 * limitations under the License.
mbed_official 255:20b371a9491b 15 */
mbed_official 255:20b371a9491b 16 #include "mbed_assert.h"
mbed_official 255:20b371a9491b 17 #include "analogin_api.h"
mbed_official 255:20b371a9491b 18
mbed_official 255:20b371a9491b 19 #include "cmsis.h"
mbed_official 255:20b371a9491b 20 #include "pinmap.h"
mbed_official 255:20b371a9491b 21 #include "clk_freqs.h"
mbed_official 255:20b371a9491b 22
mbed_official 255:20b371a9491b 23 #define MAX_FADC 6000000
mbed_official 255:20b371a9491b 24
mbed_official 255:20b371a9491b 25 static const PinMap PinMap_ADC[] = {
mbed_official 255:20b371a9491b 26 {PTC2, ADC0_SE4b, 0},
mbed_official 255:20b371a9491b 27 {PTD1, ADC0_SE5b, 0},
mbed_official 255:20b371a9491b 28 {PTD5, ADC0_SE6b, 0},
mbed_official 255:20b371a9491b 29 {PTD6, ADC0_SE7b, 0},
mbed_official 255:20b371a9491b 30 {PTB0, ADC0_SE8, 0},
mbed_official 255:20b371a9491b 31 {PTB1, ADC0_SE9, 0},
mbed_official 255:20b371a9491b 32 {PTB2, ADC0_SE12, 0},
mbed_official 255:20b371a9491b 33 {PTB3, ADC0_SE13, 0},
mbed_official 255:20b371a9491b 34 {PTC0, ADC0_SE14, 0},
mbed_official 255:20b371a9491b 35 {PTC1, ADC0_SE15, 0},
mbed_official 255:20b371a9491b 36 {NC, NC, 0}
mbed_official 255:20b371a9491b 37 };
mbed_official 255:20b371a9491b 38
mbed_official 255:20b371a9491b 39 void analogin_init(analogin_t *obj, PinName pin) {
mbed_official 255:20b371a9491b 40 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
mbed_official 255:20b371a9491b 41 MBED_ASSERT(obj->adc != (ADCName)NC);
mbed_official 255:20b371a9491b 42
mbed_official 255:20b371a9491b 43 SIM->SCGC6 |= SIM_SCGC6_ADC0_MASK;
mbed_official 255:20b371a9491b 44
mbed_official 255:20b371a9491b 45 uint32_t port = (uint32_t)pin >> PORT_SHIFT;
mbed_official 255:20b371a9491b 46 SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port);
mbed_official 255:20b371a9491b 47
mbed_official 255:20b371a9491b 48 // bus clk
mbed_official 255:20b371a9491b 49 uint32_t PCLK = bus_frequency();
mbed_official 255:20b371a9491b 50 uint32_t clkdiv;
mbed_official 255:20b371a9491b 51 for (clkdiv = 0; clkdiv < 4; clkdiv++) {
mbed_official 255:20b371a9491b 52 if ((PCLK >> clkdiv) <= MAX_FADC)
mbed_official 255:20b371a9491b 53 break;
mbed_official 255:20b371a9491b 54 }
mbed_official 255:20b371a9491b 55 if (clkdiv == 4) //Set max div
mbed_official 255:20b371a9491b 56 clkdiv = 0x7;
mbed_official 255:20b371a9491b 57
mbed_official 255:20b371a9491b 58 ADC0->SC1[1] = ADC_SC1_ADCH(obj->adc);
mbed_official 255:20b371a9491b 59
mbed_official 255:20b371a9491b 60 ADC0->CFG1 = ADC_CFG1_ADLPC_MASK // Low-Power Configuration
mbed_official 255:20b371a9491b 61 | ADC_CFG1_ADIV(clkdiv & 0x3) // Clock Divide Select
mbed_official 255:20b371a9491b 62 | ADC_CFG1_ADLSMP_MASK // Long Sample Time
mbed_official 255:20b371a9491b 63 | ADC_CFG1_MODE(3) // (16)bits Resolution
mbed_official 255:20b371a9491b 64 | ADC_CFG1_ADICLK(clkdiv >> 2); // Input Clock
mbed_official 255:20b371a9491b 65
mbed_official 255:20b371a9491b 66 ADC0->CFG2 = ADC_CFG2_MUXSEL_MASK // ADxxb or ADxxa channels
mbed_official 255:20b371a9491b 67 | ADC_CFG2_ADACKEN_MASK // Asynchronous Clock Output Enable
mbed_official 255:20b371a9491b 68 | ADC_CFG2_ADHSC_MASK // High-Speed Configuration
mbed_official 255:20b371a9491b 69 | ADC_CFG2_ADLSTS(0); // Long Sample Time Select
mbed_official 255:20b371a9491b 70
mbed_official 255:20b371a9491b 71 ADC0->SC2 = ADC_SC2_REFSEL(0); // Default Voltage Reference
mbed_official 255:20b371a9491b 72
mbed_official 255:20b371a9491b 73 ADC0->SC3 = ADC_SC3_AVGE_MASK // Hardware Average Enable
mbed_official 255:20b371a9491b 74 | ADC_SC3_AVGS(0); // 4 Samples Averaged
mbed_official 255:20b371a9491b 75
mbed_official 255:20b371a9491b 76 pinmap_pinout(pin, PinMap_ADC);
mbed_official 255:20b371a9491b 77 }
mbed_official 255:20b371a9491b 78
mbed_official 255:20b371a9491b 79 uint16_t analogin_read_u16(analogin_t *obj) {
mbed_official 255:20b371a9491b 80 // start conversion
mbed_official 255:20b371a9491b 81 ADC0->SC1[0] = ADC_SC1_ADCH(obj->adc);
mbed_official 255:20b371a9491b 82
mbed_official 255:20b371a9491b 83 // Wait Conversion Complete
mbed_official 255:20b371a9491b 84 while ((ADC0->SC1[0] & ADC_SC1_COCO_MASK) != ADC_SC1_COCO_MASK);
mbed_official 255:20b371a9491b 85
mbed_official 255:20b371a9491b 86 return (uint16_t)ADC0->R[0];
mbed_official 255:20b371a9491b 87 }
mbed_official 255:20b371a9491b 88
mbed_official 255:20b371a9491b 89 float analogin_read(analogin_t *obj) {
mbed_official 255:20b371a9491b 90 uint16_t value = analogin_read_u16(obj);
mbed_official 255:20b371a9491b 91 return (float)value * (1.0f / (float)0xFFFF);
mbed_official 255:20b371a9491b 92 }
mbed_official 255:20b371a9491b 93