Ermanno Brusadin / mbed

mbed library sources

Dependents:   FRDM-KL46Z_LCD_Test FRDM-KL46Z_LCD_Test FRDM-KL46Z_Plantilla FRDM-KL46Z_Plantilla ... more

targets/hal/TARGET_Freescale/TARGET_KLXX/analogin_api.c@0:6bc4ac881c8e, 2016-07-28 (annotated)

Committer:
ebrus
Date:
Thu Jul 28 15:56:34 2016 +0000
Revision:
0:6bc4ac881c8e
1;

Who changed what in which revision?

UserRevisionLine numberNew contents of line
ebrus 0:6bc4ac881c8e 1 /* mbed Microcontroller Library
ebrus 0:6bc4ac881c8e 2 * Copyright (c) 2006-2013 ARM Limited
ebrus 0:6bc4ac881c8e 3 *
ebrus 0:6bc4ac881c8e 4 * Licensed under the Apache License, Version 2.0 (the "License");
ebrus 0:6bc4ac881c8e 5 * you may not use this file except in compliance with the License.
ebrus 0:6bc4ac881c8e 6 * You may obtain a copy of the License at
ebrus 0:6bc4ac881c8e 7 *
ebrus 0:6bc4ac881c8e 8 * http://www.apache.org/licenses/LICENSE-2.0
ebrus 0:6bc4ac881c8e 9 *
ebrus 0:6bc4ac881c8e 10 * Unless required by applicable law or agreed to in writing, software
ebrus 0:6bc4ac881c8e 11 * distributed under the License is distributed on an "AS IS" BASIS,
ebrus 0:6bc4ac881c8e 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
ebrus 0:6bc4ac881c8e 13 * See the License for the specific language governing permissions and
ebrus 0:6bc4ac881c8e 14 * limitations under the License.
ebrus 0:6bc4ac881c8e 15 */
ebrus 0:6bc4ac881c8e 16 #include "mbed_assert.h"
ebrus 0:6bc4ac881c8e 17 #include "analogin_api.h"
ebrus 0:6bc4ac881c8e 18
ebrus 0:6bc4ac881c8e 19 #include "cmsis.h"
ebrus 0:6bc4ac881c8e 20 #include "pinmap.h"
ebrus 0:6bc4ac881c8e 21 #include "clk_freqs.h"
ebrus 0:6bc4ac881c8e 22 #include "PeripheralPins.h"
ebrus 0:6bc4ac881c8e 23
ebrus 0:6bc4ac881c8e 24 #define MAX_FADC 6000000
ebrus 0:6bc4ac881c8e 25 #define CHANNELS_A_SHIFT 5
ebrus 0:6bc4ac881c8e 26
ebrus 0:6bc4ac881c8e 27
ebrus 0:6bc4ac881c8e 28 void analogin_init(analogin_t *obj, PinName pin) {
ebrus 0:6bc4ac881c8e 29 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
ebrus 0:6bc4ac881c8e 30 MBED_ASSERT(obj->adc != (ADCName)NC);
ebrus 0:6bc4ac881c8e 31
ebrus 0:6bc4ac881c8e 32 SIM->SCGC6 |= SIM_SCGC6_ADC0_MASK;
ebrus 0:6bc4ac881c8e 33
ebrus 0:6bc4ac881c8e 34 uint32_t port = (uint32_t)pin >> PORT_SHIFT;
ebrus 0:6bc4ac881c8e 35 SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port);
ebrus 0:6bc4ac881c8e 36
ebrus 0:6bc4ac881c8e 37 uint32_t cfg2_muxsel = ADC_CFG2_MUXSEL_MASK;
ebrus 0:6bc4ac881c8e 38 if (obj->adc & (1 << CHANNELS_A_SHIFT)) {
ebrus 0:6bc4ac881c8e 39 cfg2_muxsel = 0;
ebrus 0:6bc4ac881c8e 40 }
ebrus 0:6bc4ac881c8e 41
ebrus 0:6bc4ac881c8e 42 // bus clk
ebrus 0:6bc4ac881c8e 43 uint32_t PCLK = bus_frequency();
ebrus 0:6bc4ac881c8e 44 uint32_t clkdiv;
ebrus 0:6bc4ac881c8e 45 for (clkdiv = 0; clkdiv < 4; clkdiv++) {
ebrus 0:6bc4ac881c8e 46 if ((PCLK >> clkdiv) <= MAX_FADC)
ebrus 0:6bc4ac881c8e 47 break;
ebrus 0:6bc4ac881c8e 48 }
ebrus 0:6bc4ac881c8e 49 if (clkdiv == 4) //Set max div
ebrus 0:6bc4ac881c8e 50 clkdiv = 0x7;
ebrus 0:6bc4ac881c8e 51
ebrus 0:6bc4ac881c8e 52 ADC0->SC1[1] = ADC_SC1_ADCH(obj->adc & ~(1 << CHANNELS_A_SHIFT));
ebrus 0:6bc4ac881c8e 53
ebrus 0:6bc4ac881c8e 54 ADC0->CFG1 = ADC_CFG1_ADLPC_MASK // Low-Power Configuration
ebrus 0:6bc4ac881c8e 55 | ADC_CFG1_ADIV(clkdiv & 0x3) // Clock Divide Select: (Input Clock)/8
ebrus 0:6bc4ac881c8e 56 | ADC_CFG1_ADLSMP_MASK // Long Sample Time
ebrus 0:6bc4ac881c8e 57 | ADC_CFG1_MODE(3) // (16)bits Resolution
ebrus 0:6bc4ac881c8e 58 | ADC_CFG1_ADICLK(clkdiv >> 2); // Input Clock: (Bus Clock)/2
ebrus 0:6bc4ac881c8e 59
ebrus 0:6bc4ac881c8e 60 ADC0->CFG2 = cfg2_muxsel // ADxxb or ADxxa channels
ebrus 0:6bc4ac881c8e 61 | ADC_CFG2_ADACKEN_MASK // Asynchronous Clock Output Enable
ebrus 0:6bc4ac881c8e 62 | ADC_CFG2_ADHSC_MASK // High-Speed Configuration
ebrus 0:6bc4ac881c8e 63 | ADC_CFG2_ADLSTS(0); // Long Sample Time Select
ebrus 0:6bc4ac881c8e 64
ebrus 0:6bc4ac881c8e 65 ADC0->SC2 = ADC_SC2_REFSEL(0); // Default Voltage Reference
ebrus 0:6bc4ac881c8e 66
ebrus 0:6bc4ac881c8e 67 ADC0->SC3 = ADC_SC3_AVGE_MASK // Hardware Average Enable
ebrus 0:6bc4ac881c8e 68 | ADC_SC3_AVGS(0); // 4 Samples Averaged
ebrus 0:6bc4ac881c8e 69
ebrus 0:6bc4ac881c8e 70 pinmap_pinout(pin, PinMap_ADC);
ebrus 0:6bc4ac881c8e 71 }
ebrus 0:6bc4ac881c8e 72
ebrus 0:6bc4ac881c8e 73 uint16_t analogin_read_u16(analogin_t *obj) {
ebrus 0:6bc4ac881c8e 74 // start conversion
ebrus 0:6bc4ac881c8e 75 ADC0->SC1[0] = ADC_SC1_ADCH(obj->adc & ~(1 << CHANNELS_A_SHIFT));
ebrus 0:6bc4ac881c8e 76
ebrus 0:6bc4ac881c8e 77 // Wait Conversion Complete
ebrus 0:6bc4ac881c8e 78 while ((ADC0->SC1[0] & ADC_SC1_COCO_MASK) != ADC_SC1_COCO_MASK);
ebrus 0:6bc4ac881c8e 79
ebrus 0:6bc4ac881c8e 80 // Return value
ebrus 0:6bc4ac881c8e 81 return (uint16_t)ADC0->R[0];
ebrus 0:6bc4ac881c8e 82 }
ebrus 0:6bc4ac881c8e 83
ebrus 0:6bc4ac881c8e 84 float analogin_read(analogin_t *obj) {
ebrus 0:6bc4ac881c8e 85 uint16_t value = analogin_read_u16(obj);
ebrus 0:6bc4ac881c8e 86 return (float)value * (1.0f / (float)0xFFFF);
ebrus 0:6bc4ac881c8e 87 }
ebrus 0:6bc4ac881c8e 88