mbed official / mbed-dev

mbed library sources. Supersedes mbed-src.

Dependents:   Nucleo_Hello_Encoder BLE_iBeaconScan AM1805_DEMO DISCO-F429ZI_ExportTemplate1 ... more

targets/TARGET_NORDIC/TARGET_MCU_NRF51822/analogin_api.c@189:f392fc9709a3, 2019-02-20 (annotated)

Committer:
AnnaBridge
Date:
Wed Feb 20 22:31:08 2019 +0000
Revision:
189:f392fc9709a3
Parent:
151:5eaa88a5bcc7 
mbed library release version 165

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /* mbed Microcontroller Library
<> 144:ef7eb2e8f9f7 2 * Copyright (c) 2006-2013 ARM Limited
<> 144:ef7eb2e8f9f7 3 *
<> 144:ef7eb2e8f9f7 4 * Licensed under the Apache License, Version 2.0 (the "License");
<> 144:ef7eb2e8f9f7 5 * you may not use this file except in compliance with the License.
<> 144:ef7eb2e8f9f7 6 * You may obtain a copy of the License at
<> 144:ef7eb2e8f9f7 7 *
<> 144:ef7eb2e8f9f7 8 * http://www.apache.org/licenses/LICENSE-2.0
<> 144:ef7eb2e8f9f7 9 *
<> 144:ef7eb2e8f9f7 10 * Unless required by applicable law or agreed to in writing, software
<> 144:ef7eb2e8f9f7 11 * distributed under the License is distributed on an "AS IS" BASIS,
<> 144:ef7eb2e8f9f7 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
<> 144:ef7eb2e8f9f7 13 * See the License for the specific language governing permissions and
<> 144:ef7eb2e8f9f7 14 * limitations under the License.
<> 144:ef7eb2e8f9f7 15 */
<> 144:ef7eb2e8f9f7 16 #include "mbed_assert.h"
<> 144:ef7eb2e8f9f7 17 #include "analogin_api.h"
<> 144:ef7eb2e8f9f7 18 #include "cmsis.h"
<> 144:ef7eb2e8f9f7 19 #include "pinmap.h"
<> 144:ef7eb2e8f9f7 20
<> 144:ef7eb2e8f9f7 21 #define ANALOGIN_MEDIAN_FILTER 1
<> 144:ef7eb2e8f9f7 22 #define ADC_10BIT_RANGE 0x3FF
<> 144:ef7eb2e8f9f7 23 #define ADC_RANGE ADC_10BIT_RANGE
<> 144:ef7eb2e8f9f7 24
<> 144:ef7eb2e8f9f7 25 static const PinMap PinMap_ADC[] = {
<> 151:5eaa88a5bcc7 26 {P0_1, ADC0_0, 4},
<> 151:5eaa88a5bcc7 27 {P0_2, ADC0_0, 8},
<> 151:5eaa88a5bcc7 28 {P0_3, ADC0_0, 16},
<> 151:5eaa88a5bcc7 29 {P0_4, ADC0_0, 32},
<> 151:5eaa88a5bcc7 30 {P0_5, ADC0_0, 64},
<> 151:5eaa88a5bcc7 31 {P0_6, ADC0_0, 128},
<> 144:ef7eb2e8f9f7 32 #ifndef TARGET_NRF51_DONGLE
<> 151:5eaa88a5bcc7 33 {P0_26, ADC0_0, 1},
<> 151:5eaa88a5bcc7 34 {P0_27, ADC0_0, 2},
<> 144:ef7eb2e8f9f7 35 #endif
<> 144:ef7eb2e8f9f7 36 {NC, NC, 0}
<> 144:ef7eb2e8f9f7 37 };
<> 144:ef7eb2e8f9f7 38
<> 144:ef7eb2e8f9f7 39 void analogin_init(analogin_t *obj, PinName pin)
<> 144:ef7eb2e8f9f7 40 {
<> 144:ef7eb2e8f9f7 41 int analogInputPin = 0;
<> 144:ef7eb2e8f9f7 42 const PinMap *map = PinMap_ADC;
<> 144:ef7eb2e8f9f7 43
<> 144:ef7eb2e8f9f7 44 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC); //(NRF_ADC_Type *)
<> 144:ef7eb2e8f9f7 45 MBED_ASSERT(obj->adc != (ADCName)NC);
<> 144:ef7eb2e8f9f7 46
<> 144:ef7eb2e8f9f7 47 while (map->pin != NC) {
<> 144:ef7eb2e8f9f7 48 if (map->pin == pin) {
<> 144:ef7eb2e8f9f7 49 analogInputPin = map->function;
<> 144:ef7eb2e8f9f7 50 break;
<> 144:ef7eb2e8f9f7 51 }
<> 144:ef7eb2e8f9f7 52 map++;
<> 144:ef7eb2e8f9f7 53 }
<> 144:ef7eb2e8f9f7 54 obj->adc_pin = (uint8_t)analogInputPin;
<> 144:ef7eb2e8f9f7 55
<> 144:ef7eb2e8f9f7 56 NRF_ADC->ENABLE = ADC_ENABLE_ENABLE_Enabled;
<> 144:ef7eb2e8f9f7 57 NRF_ADC->CONFIG = (ADC_CONFIG_RES_10bit << ADC_CONFIG_RES_Pos) |
<> 144:ef7eb2e8f9f7 58 (ADC_CONFIG_INPSEL_AnalogInputOneThirdPrescaling << ADC_CONFIG_INPSEL_Pos) |
<> 144:ef7eb2e8f9f7 59 (ADC_CONFIG_REFSEL_SupplyOneThirdPrescaling << ADC_CONFIG_REFSEL_Pos) |
<> 144:ef7eb2e8f9f7 60 (analogInputPin << ADC_CONFIG_PSEL_Pos) |
<> 144:ef7eb2e8f9f7 61 (ADC_CONFIG_EXTREFSEL_None << ADC_CONFIG_EXTREFSEL_Pos);
<> 144:ef7eb2e8f9f7 62 }
<> 144:ef7eb2e8f9f7 63
<> 144:ef7eb2e8f9f7 64 uint16_t analogin_read_u16(analogin_t *obj)
<> 144:ef7eb2e8f9f7 65 {
<> 144:ef7eb2e8f9f7 66 NRF_ADC->CONFIG &= ~ADC_CONFIG_PSEL_Msk;
<> 144:ef7eb2e8f9f7 67 NRF_ADC->CONFIG |= obj->adc_pin << ADC_CONFIG_PSEL_Pos;
<> 144:ef7eb2e8f9f7 68 NRF_ADC->EVENTS_END = 0;
<> 144:ef7eb2e8f9f7 69 NRF_ADC->TASKS_START = 1;
<> 144:ef7eb2e8f9f7 70
<> 144:ef7eb2e8f9f7 71 while (!NRF_ADC->EVENTS_END) {
<> 144:ef7eb2e8f9f7 72 }
<> 144:ef7eb2e8f9f7 73
<> 144:ef7eb2e8f9f7 74 return (uint16_t)NRF_ADC->RESULT; // 10 bit
<> 144:ef7eb2e8f9f7 75 }
<> 144:ef7eb2e8f9f7 76
<> 144:ef7eb2e8f9f7 77 float analogin_read(analogin_t *obj)
<> 144:ef7eb2e8f9f7 78 {
<> 144:ef7eb2e8f9f7 79 uint16_t value = analogin_read_u16(obj);
<> 144:ef7eb2e8f9f7 80 return (float)value * (1.0f / (float)ADC_RANGE);
<> 144:ef7eb2e8f9f7 81 }