Amit Gandhi / mbed-dev

test

Fork of mbed-dev by mbed official

targets/TARGET_NXP/TARGET_LPC11UXX/analogin_api.c@178:d650f5d4c87a, 2017-11-08 (annotated)

Committer:
AnnaBridge
Date:
Wed Nov 08 13:50:44 2017 +0000
Revision:
178:d650f5d4c87a
Parent:
149:156823d33999 
This updates the lib to the mbed lib v 155

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 #include "mbed_error.h"
<> 144:ef7eb2e8f9f7 21 #include "PeripheralPins.h" // For the Peripheral to Pin Definitions found in the individual Target's Platform
<> 144:ef7eb2e8f9f7 22
<> 144:ef7eb2e8f9f7 23 #define ANALOGIN_MEDIAN_FILTER 1
<> 144:ef7eb2e8f9f7 24
<> 144:ef7eb2e8f9f7 25 #define ADC_10BIT_RANGE 0x3FF
<> 144:ef7eb2e8f9f7 26 #define ADC_12BIT_RANGE 0xFFF
<> 144:ef7eb2e8f9f7 27
<> 144:ef7eb2e8f9f7 28 static inline int div_round_up(int x, int y) {
<> 144:ef7eb2e8f9f7 29 return (x + (y - 1)) / y;
<> 144:ef7eb2e8f9f7 30 }
<> 144:ef7eb2e8f9f7 31
<> 144:ef7eb2e8f9f7 32 #define LPC_IOCON0_BASE (LPC_IOCON_BASE)
<> 144:ef7eb2e8f9f7 33 #define LPC_IOCON1_BASE (LPC_IOCON_BASE + 0x60)
<> 144:ef7eb2e8f9f7 34
<> 144:ef7eb2e8f9f7 35 #define ADC_RANGE ADC_10BIT_RANGE
<> 144:ef7eb2e8f9f7 36
<> 144:ef7eb2e8f9f7 37 void analogin_init(analogin_t *obj, PinName pin) {
<> 144:ef7eb2e8f9f7 38 obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
<> 144:ef7eb2e8f9f7 39 MBED_ASSERT(obj->adc != (ADCName)NC);
<> 144:ef7eb2e8f9f7 40
<> 144:ef7eb2e8f9f7 41 // Power up ADC
<> 144:ef7eb2e8f9f7 42 LPC_SYSCON->PDRUNCFG &= ~ (1 << 4);
<> 144:ef7eb2e8f9f7 43 LPC_SYSCON->SYSAHBCLKCTRL |= ((uint32_t)1 << 13);
<> 144:ef7eb2e8f9f7 44
<> 144:ef7eb2e8f9f7 45 uint32_t pin_number = (uint32_t)pin;
<> 144:ef7eb2e8f9f7 46 __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));
<> 144:ef7eb2e8f9f7 47
<> 144:ef7eb2e8f9f7 48 // set pin to ADC mode
<> 144:ef7eb2e8f9f7 49 *reg &= ~(1 << 7); // set ADMODE = 0 (analog mode)
<> 144:ef7eb2e8f9f7 50
<> 144:ef7eb2e8f9f7 51 uint32_t PCLK = SystemCoreClock;
<> 144:ef7eb2e8f9f7 52 uint32_t MAX_ADC_CLK = 4500000;
<> 144:ef7eb2e8f9f7 53 uint32_t clkdiv = div_round_up(PCLK, MAX_ADC_CLK) - 1;
<> 144:ef7eb2e8f9f7 54
<> 144:ef7eb2e8f9f7 55 LPC_ADC->CR = (0 << 0) // no channels selected
<> 144:ef7eb2e8f9f7 56 | (clkdiv << 8) // max of 4.5MHz
<> 144:ef7eb2e8f9f7 57 | (0 << 16) // BURST = 0, software controlled
<> 144:ef7eb2e8f9f7 58 | ( 0 << 17 ); // CLKS = 0, not applicable
<> 144:ef7eb2e8f9f7 59
<> 144:ef7eb2e8f9f7 60 pinmap_pinout(pin, PinMap_ADC);
<> 144:ef7eb2e8f9f7 61 }
<> 144:ef7eb2e8f9f7 62
<> 144:ef7eb2e8f9f7 63 static inline uint32_t adc_read(analogin_t *obj) {
<> 144:ef7eb2e8f9f7 64 // Select the appropriate channel and start conversion
<> 144:ef7eb2e8f9f7 65 LPC_ADC->CR &= ~0xFF;
<> 144:ef7eb2e8f9f7 66 LPC_ADC->CR |= 1 << (int)obj->adc;
<> 144:ef7eb2e8f9f7 67 LPC_ADC->CR |= 1 << 24;
<> 144:ef7eb2e8f9f7 68
<> 144:ef7eb2e8f9f7 69 // Repeatedly get the sample data until DONE bit
<> 144:ef7eb2e8f9f7 70 unsigned int data;
<> 144:ef7eb2e8f9f7 71 do {
<> 144:ef7eb2e8f9f7 72 data = LPC_ADC->GDR;
<> 144:ef7eb2e8f9f7 73 } while ((data & ((unsigned int)1 << 31)) == 0);
<> 144:ef7eb2e8f9f7 74
<> 144:ef7eb2e8f9f7 75 // Stop conversion
<> 144:ef7eb2e8f9f7 76 LPC_ADC->CR &= ~(1 << 24);
<> 144:ef7eb2e8f9f7 77
<> 144:ef7eb2e8f9f7 78 return (data >> 6) & ADC_RANGE; // 10 bit
<> 144:ef7eb2e8f9f7 79 }
<> 144:ef7eb2e8f9f7 80
<> 144:ef7eb2e8f9f7 81 static inline void order(uint32_t *a, uint32_t *b) {
<> 144:ef7eb2e8f9f7 82 if (*a > *b) {
<> 144:ef7eb2e8f9f7 83 uint32_t t = *a;
<> 144:ef7eb2e8f9f7 84 *a = *b;
<> 144:ef7eb2e8f9f7 85 *b = t;
<> 144:ef7eb2e8f9f7 86 }
<> 144:ef7eb2e8f9f7 87 }
<> 144:ef7eb2e8f9f7 88
<> 144:ef7eb2e8f9f7 89 static inline uint32_t adc_read_u32(analogin_t *obj) {
<> 144:ef7eb2e8f9f7 90 uint32_t value;
<> 144:ef7eb2e8f9f7 91 #if ANALOGIN_MEDIAN_FILTER
<> 144:ef7eb2e8f9f7 92 uint32_t v1 = adc_read(obj);
<> 144:ef7eb2e8f9f7 93 uint32_t v2 = adc_read(obj);
<> 144:ef7eb2e8f9f7 94 uint32_t v3 = adc_read(obj);
<> 144:ef7eb2e8f9f7 95 order(&v1, &v2);
<> 144:ef7eb2e8f9f7 96 order(&v2, &v3);
<> 144:ef7eb2e8f9f7 97 order(&v1, &v2);
<> 144:ef7eb2e8f9f7 98 value = v2;
<> 144:ef7eb2e8f9f7 99 #else
<> 144:ef7eb2e8f9f7 100 value = adc_read(obj);
<> 144:ef7eb2e8f9f7 101 #endif
<> 144:ef7eb2e8f9f7 102 return value;
<> 144:ef7eb2e8f9f7 103 }
<> 144:ef7eb2e8f9f7 104
<> 144:ef7eb2e8f9f7 105 uint16_t analogin_read_u16(analogin_t *obj) {
<> 144:ef7eb2e8f9f7 106 uint32_t value = adc_read_u32(obj);
<> 144:ef7eb2e8f9f7 107
<> 144:ef7eb2e8f9f7 108 return (value << 6) | ((value >> 4) & 0x003F); // 10 bit
<> 144:ef7eb2e8f9f7 109 }
<> 144:ef7eb2e8f9f7 110
<> 144:ef7eb2e8f9f7 111 float analogin_read(analogin_t *obj) {
<> 144:ef7eb2e8f9f7 112 uint32_t value = adc_read_u32(obj);
<> 144:ef7eb2e8f9f7 113 return (float)value * (1.0f / (float)ADC_RANGE);
<> 144:ef7eb2e8f9f7 114 }