mbed official / mbed-src

mbed library sources

Dependents:   Encrypted my_mbed lklk CyaSSL_DTLS_Cellular ... more

Superseded

This library was superseded by mbed-dev - https://os.mbed.com/users/mbed_official/code/mbed-dev/.

Development branch of the mbed library sources. This library is kept in synch with the latest changes from the mbed SDK and it is not guaranteed to work.

If you are looking for a stable and tested release, please import one of the official mbed library releases:

Import librarymbed

The official Mbed 2 C/C++ SDK provides the software platform and libraries to build your applications.

Last commit 20 Feb 2019 by mbed official

targets/hal/TARGET_NXP/TARGET_LPC11UXX/analogin_api.c@19:398f4c622e1b, 2013-08-19 (annotated)

Committer:
bogdanm
Date:
Mon Aug 19 18:17:02 2013 +0300
Revision:
19:398f4c622e1b
Parent:
13:0645d8841f51
Child:
227:7bd0639b8911
Sync with official mbed library release 66

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 10:3bc89ef62ce7 1 /* mbed Microcontroller Library
emilmont 10:3bc89ef62ce7 2 * Copyright (c) 2006-2013 ARM Limited
emilmont 10:3bc89ef62ce7 3 *
emilmont 10:3bc89ef62ce7 4 * Licensed under the Apache License, Version 2.0 (the "License");
emilmont 10:3bc89ef62ce7 5 * you may not use this file except in compliance with the License.
emilmont 10:3bc89ef62ce7 6 * You may obtain a copy of the License at
emilmont 10:3bc89ef62ce7 7 *
emilmont 10:3bc89ef62ce7 8 * http://www.apache.org/licenses/LICENSE-2.0
emilmont 10:3bc89ef62ce7 9 *
emilmont 10:3bc89ef62ce7 10 * Unless required by applicable law or agreed to in writing, software
emilmont 10:3bc89ef62ce7 11 * distributed under the License is distributed on an "AS IS" BASIS,
emilmont 10:3bc89ef62ce7 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
emilmont 10:3bc89ef62ce7 13 * See the License for the specific language governing permissions and
emilmont 10:3bc89ef62ce7 14 * limitations under the License.
emilmont 10:3bc89ef62ce7 15 */
emilmont 10:3bc89ef62ce7 16 #include "analogin_api.h"
emilmont 10:3bc89ef62ce7 17 #include "cmsis.h"
emilmont 10:3bc89ef62ce7 18 #include "pinmap.h"
emilmont 10:3bc89ef62ce7 19 #include "error.h"
emilmont 10:3bc89ef62ce7 20
emilmont 10:3bc89ef62ce7 21 #define ANALOGIN_MEDIAN_FILTER 1
emilmont 10:3bc89ef62ce7 22
emilmont 10:3bc89ef62ce7 23 #define ADC_10BIT_RANGE 0x3FF
emilmont 10:3bc89ef62ce7 24 #define ADC_12BIT_RANGE 0xFFF
emilmont 10:3bc89ef62ce7 25
emilmont 10:3bc89ef62ce7 26 static inline int div_round_up(int x, int y) {
emilmont 10:3bc89ef62ce7 27 return (x + (y - 1)) / y;
emilmont 10:3bc89ef62ce7 28 }
emilmont 10:3bc89ef62ce7 29
emilmont 10:3bc89ef62ce7 30 static const PinMap PinMap_ADC[] = {
emilmont 10:3bc89ef62ce7 31 {P0_11, ADC0_0, 0x02},
emilmont 10:3bc89ef62ce7 32 {P0_12, ADC0_1, 0x02},
emilmont 10:3bc89ef62ce7 33 {P0_13, ADC0_2, 0x02},
emilmont 10:3bc89ef62ce7 34 {P0_14, ADC0_3, 0x02},
emilmont 10:3bc89ef62ce7 35 {P0_15, ADC0_4, 0x02},
emilmont 10:3bc89ef62ce7 36 {P0_16, ADC0_5, 0x01},
emilmont 10:3bc89ef62ce7 37 {P0_22, ADC0_6, 0x01},
emilmont 10:3bc89ef62ce7 38 {P0_23, ADC0_7, 0x01},
emilmont 10:3bc89ef62ce7 39 {NC , NC , 0 }
emilmont 10:3bc89ef62ce7 40 };
emilmont 10:3bc89ef62ce7 41
emilmont 10:3bc89ef62ce7 42 #define LPC_IOCON0_BASE (LPC_IOCON_BASE)
emilmont 10:3bc89ef62ce7 43 #define LPC_IOCON1_BASE (LPC_IOCON_BASE + 0x60)
emilmont 10:3bc89ef62ce7 44
emilmont 10:3bc89ef62ce7 45 #define ADC_RANGE ADC_10BIT_RANGE
emilmont 10:3bc89ef62ce7 46
emilmont 10:3bc89ef62ce7 47 void analogin_init(analogin_t *obj, PinName pin) {
emilmont 10:3bc89ef62ce7 48 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
bogdanm 19:398f4c622e1b 49 if (obj->adc == (ADCName)NC) {
emilmont 10:3bc89ef62ce7 50 error("ADC pin mapping failed");
emilmont 10:3bc89ef62ce7 51 }
emilmont 10:3bc89ef62ce7 52
emilmont 10:3bc89ef62ce7 53 // Power up ADC
emilmont 10:3bc89ef62ce7 54 LPC_SYSCON->PDRUNCFG &= ~ (1 << 4);
emilmont 10:3bc89ef62ce7 55 LPC_SYSCON->SYSAHBCLKCTRL |= ((uint32_t)1 << 13);
emilmont 10:3bc89ef62ce7 56
emilmont 10:3bc89ef62ce7 57 uint32_t pin_number = (uint32_t)pin;
emilmont 10:3bc89ef62ce7 58 __IO uint32_t *reg = (pin_number < 32) ? (__IO uint32_t*)(LPC_IOCON0_BASE + 4 * pin_number) : (__IO uint32_t*)(LPC_IOCON1_BASE + 4 * (pin_number - 32));
emilmont 10:3bc89ef62ce7 59
emilmont 10:3bc89ef62ce7 60 // set pin to ADC mode
emilmont 10:3bc89ef62ce7 61 *reg &= ~(1 << 7); // set ADMODE = 0 (analog mode)
emilmont 10:3bc89ef62ce7 62
emilmont 10:3bc89ef62ce7 63 uint32_t PCLK = SystemCoreClock;
emilmont 10:3bc89ef62ce7 64 uint32_t MAX_ADC_CLK = 4500000;
emilmont 10:3bc89ef62ce7 65 uint32_t clkdiv = div_round_up(PCLK, MAX_ADC_CLK) - 1;
emilmont 10:3bc89ef62ce7 66
emilmont 10:3bc89ef62ce7 67 LPC_ADC->CR = (0 << 0) // no channels selected
emilmont 10:3bc89ef62ce7 68 | (clkdiv << 8) // max of 4.5MHz
emilmont 10:3bc89ef62ce7 69 | (0 << 16) // BURST = 0, software controlled
emilmont 10:3bc89ef62ce7 70 | ( 0 << 17 ); // CLKS = 0, not applicable
emilmont 10:3bc89ef62ce7 71
emilmont 10:3bc89ef62ce7 72 pinmap_pinout(pin, PinMap_ADC);
emilmont 10:3bc89ef62ce7 73 }
emilmont 10:3bc89ef62ce7 74
emilmont 10:3bc89ef62ce7 75 static inline uint32_t adc_read(analogin_t *obj) {
emilmont 10:3bc89ef62ce7 76 // Select the appropriate channel and start conversion
emilmont 10:3bc89ef62ce7 77 LPC_ADC->CR &= ~0xFF;
emilmont 10:3bc89ef62ce7 78 LPC_ADC->CR |= 1 << (int)obj->adc;
emilmont 10:3bc89ef62ce7 79 LPC_ADC->CR |= 1 << 24;
emilmont 10:3bc89ef62ce7 80
emilmont 10:3bc89ef62ce7 81 // Repeatedly get the sample data until DONE bit
emilmont 10:3bc89ef62ce7 82 unsigned int data;
emilmont 10:3bc89ef62ce7 83 do {
emilmont 10:3bc89ef62ce7 84 data = LPC_ADC->GDR;
emilmont 10:3bc89ef62ce7 85 } while ((data & ((unsigned int)1 << 31)) == 0);
emilmont 10:3bc89ef62ce7 86
emilmont 10:3bc89ef62ce7 87 // Stop conversion
emilmont 10:3bc89ef62ce7 88 LPC_ADC->CR &= ~(1 << 24);
emilmont 10:3bc89ef62ce7 89
emilmont 10:3bc89ef62ce7 90 return (data >> 6) & ADC_RANGE; // 10 bit
emilmont 10:3bc89ef62ce7 91 }
emilmont 10:3bc89ef62ce7 92
emilmont 10:3bc89ef62ce7 93 static inline void order(uint32_t *a, uint32_t *b) {
emilmont 10:3bc89ef62ce7 94 if (*a > *b) {
emilmont 10:3bc89ef62ce7 95 uint32_t t = *a;
emilmont 10:3bc89ef62ce7 96 *a = *b;
emilmont 10:3bc89ef62ce7 97 *b = t;
emilmont 10:3bc89ef62ce7 98 }
emilmont 10:3bc89ef62ce7 99 }
emilmont 10:3bc89ef62ce7 100
emilmont 10:3bc89ef62ce7 101 static inline uint32_t adc_read_u32(analogin_t *obj) {
emilmont 10:3bc89ef62ce7 102 uint32_t value;
emilmont 10:3bc89ef62ce7 103 #if ANALOGIN_MEDIAN_FILTER
emilmont 10:3bc89ef62ce7 104 uint32_t v1 = adc_read(obj);
emilmont 10:3bc89ef62ce7 105 uint32_t v2 = adc_read(obj);
emilmont 10:3bc89ef62ce7 106 uint32_t v3 = adc_read(obj);
emilmont 10:3bc89ef62ce7 107 order(&v1, &v2);
emilmont 10:3bc89ef62ce7 108 order(&v2, &v3);
emilmont 10:3bc89ef62ce7 109 order(&v1, &v2);
emilmont 10:3bc89ef62ce7 110 value = v2;
emilmont 10:3bc89ef62ce7 111 #else
emilmont 10:3bc89ef62ce7 112 value = adc_read(obj);
emilmont 10:3bc89ef62ce7 113 #endif
emilmont 10:3bc89ef62ce7 114 return value;
emilmont 10:3bc89ef62ce7 115 }
emilmont 10:3bc89ef62ce7 116
emilmont 10:3bc89ef62ce7 117 uint16_t analogin_read_u16(analogin_t *obj) {
emilmont 10:3bc89ef62ce7 118 uint32_t value = adc_read_u32(obj);
emilmont 10:3bc89ef62ce7 119
emilmont 10:3bc89ef62ce7 120 return (value << 6) | ((value >> 4) & 0x003F); // 10 bit
emilmont 10:3bc89ef62ce7 121 }
emilmont 10:3bc89ef62ce7 122
emilmont 10:3bc89ef62ce7 123 float analogin_read(analogin_t *obj) {
emilmont 10:3bc89ef62ce7 124 uint32_t value = adc_read_u32(obj);
emilmont 10:3bc89ef62ce7 125 return (float)value * (1.0f / (float)ADC_RANGE);
emilmont 10:3bc89ef62ce7 126 }