Johannes Stratmann / mbed-dev

added prescaler for 16 bit pwm in LPC1347 target

Fork of mbed-dev by mbed official

targets/hal/TARGET_ONSEMI/TARGET_NCS36510/analogin_api.c@147:ba84b7dc41a7, 2016-09-10 (annotated)

Committer:
JojoS
Date:
Sat Sep 10 15:32:04 2016 +0000
Revision:
147:ba84b7dc41a7
Parent:
144:ef7eb2e8f9f7 
added prescaler for 16 bit timers (solution as in LPC11xx), default prescaler 31 for max 28 ms period time

Who changed what in which revision?

UserRevisionLine numberNew contents of line
<> 144:ef7eb2e8f9f7 1 /**
<> 144:ef7eb2e8f9f7 2 ******************************************************************************
<> 144:ef7eb2e8f9f7 3 * @file adc_sar.c
<> 144:ef7eb2e8f9f7 4 * @brief Implementation of a SAR ADC driver
<> 144:ef7eb2e8f9f7 5 * @internal
<> 144:ef7eb2e8f9f7 6 * @author ON Semiconductor
<> 144:ef7eb2e8f9f7 7 * $Rev:
<> 144:ef7eb2e8f9f7 8 * $Date:
<> 144:ef7eb2e8f9f7 9 ******************************************************************************
<> 144:ef7eb2e8f9f7 10 * @copyright (c) 2012 ON Semiconductor. All rights reserved.
<> 144:ef7eb2e8f9f7 11 * ON Semiconductor is supplying this software for use with ON Semiconductor
<> 144:ef7eb2e8f9f7 12 * processor based microcontrollers only.
<> 144:ef7eb2e8f9f7 13 *
<> 144:ef7eb2e8f9f7 14 * THIS SOFTWARE IS PROVIDED "AS IS". NO WARRANTIES, WHETHER EXPRESS, IMPLIED
<> 144:ef7eb2e8f9f7 15 * OR STATUTORY, INCLUDING, BUT NOT LIMITED TO, IMPLIED WARRANTIES OF
<> 144:ef7eb2e8f9f7 16 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE APPLY TO THIS SOFTWARE.
<> 144:ef7eb2e8f9f7 17 * ON SEMICONDUCTOR SHALL NOT, IN ANY CIRCUMSTANCES, BE LIABLE FOR SPECIAL,
<> 144:ef7eb2e8f9f7 18 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, FOR ANY REASON WHATSOEVER.
<> 144:ef7eb2e8f9f7 19 * @endinternal
<> 144:ef7eb2e8f9f7 20 *
<> 144:ef7eb2e8f9f7 21 * @ingroup adc_sar
<> 144:ef7eb2e8f9f7 22 *
<> 144:ef7eb2e8f9f7 23 * @details
<> 144:ef7eb2e8f9f7 24 * <p>
<> 144:ef7eb2e8f9f7 25 * </p>
<> 144:ef7eb2e8f9f7 26 *
<> 144:ef7eb2e8f9f7 27 */
<> 144:ef7eb2e8f9f7 28
<> 144:ef7eb2e8f9f7 29 #include "device.h"
<> 144:ef7eb2e8f9f7 30 #include "analogin_api.h"
<> 144:ef7eb2e8f9f7 31 #include "PeripheralPins.h"
<> 144:ef7eb2e8f9f7 32 #include "mbed_assert.h"
<> 144:ef7eb2e8f9f7 33 #include "clock.h"
<> 144:ef7eb2e8f9f7 34 #include "adc_sar.h"
<> 144:ef7eb2e8f9f7 35
<> 144:ef7eb2e8f9f7 36 #if DEVICE_ANALOGIN
<> 144:ef7eb2e8f9f7 37
<> 144:ef7eb2e8f9f7 38 /**
<> 144:ef7eb2e8f9f7 39 * \defgroup hal_analogin Analogin hal functions
<> 144:ef7eb2e8f9f7 40 * @{
<> 144:ef7eb2e8f9f7 41 */
<> 144:ef7eb2e8f9f7 42
<> 144:ef7eb2e8f9f7 43 /** Initialize the analogin peripheral
<> 144:ef7eb2e8f9f7 44 *
<> 144:ef7eb2e8f9f7 45 * Configures the pin used by analogin.
<> 144:ef7eb2e8f9f7 46 * @param obj The analogin object to initialize
<> 144:ef7eb2e8f9f7 47 * @param pin The analogin pin name
<> 144:ef7eb2e8f9f7 48 */
<> 144:ef7eb2e8f9f7 49 void analogin_init(analogin_t *obj, PinName pin)
<> 144:ef7eb2e8f9f7 50 {
<> 144:ef7eb2e8f9f7 51 CLOCK_ENABLE(CLOCK_ADC);
<> 144:ef7eb2e8f9f7 52 ADCName adc;
<> 144:ef7eb2e8f9f7 53 uint8_t adc_pin = 0;
<> 144:ef7eb2e8f9f7 54
<> 144:ef7eb2e8f9f7 55 adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC);
<> 144:ef7eb2e8f9f7 56 MBED_ASSERT(adc != (ADCName)NC);
<> 144:ef7eb2e8f9f7 57
<> 144:ef7eb2e8f9f7 58 obj->adcReg = (AdcReg_pt)adc;
<> 144:ef7eb2e8f9f7 59 obj->pin = pin;
<> 144:ef7eb2e8f9f7 60 obj->pinFlag = 1;
<> 144:ef7eb2e8f9f7 61
<> 144:ef7eb2e8f9f7 62 switch (pin) {
<> 144:ef7eb2e8f9f7 63 case A0:
<> 144:ef7eb2e8f9f7 64 adc_pin=0;
<> 144:ef7eb2e8f9f7 65 break;
<> 144:ef7eb2e8f9f7 66 case A1:
<> 144:ef7eb2e8f9f7 67 adc_pin = 1;
<> 144:ef7eb2e8f9f7 68 break;
<> 144:ef7eb2e8f9f7 69 case A2:
<> 144:ef7eb2e8f9f7 70 adc_pin = 2;
<> 144:ef7eb2e8f9f7 71 break;
<> 144:ef7eb2e8f9f7 72 case A3:
<> 144:ef7eb2e8f9f7 73 adc_pin = 3;
<> 144:ef7eb2e8f9f7 74 break;
<> 144:ef7eb2e8f9f7 75 default:
<> 144:ef7eb2e8f9f7 76 break;
<> 144:ef7eb2e8f9f7 77 }
<> 144:ef7eb2e8f9f7 78
<> 144:ef7eb2e8f9f7 79 /* If no config parameters are passed on; assume default value */
<> 144:ef7eb2e8f9f7 80 if (obj->adcConf == Null) {
<> 144:ef7eb2e8f9f7 81 /* Single sample, absolute conversion, scale = 1 */
<> 144:ef7eb2e8f9f7 82 obj->adcReg->CONTROL.WORD = ((0 << ADC_CONTROL_MODE_BIT_POS) |
<> 144:ef7eb2e8f9f7 83 (1 << ADC_CONTROL_MEASTYPE_BIT_POS) |
<> 144:ef7eb2e8f9f7 84 (1 << ADC_CONTROL_INPUTSCALE_BIT_POS) |
<> 144:ef7eb2e8f9f7 85 (((uint8_t)adc_pin) << ADC_CONTROL_MEAS_CH_BIT_POS));
<> 144:ef7eb2e8f9f7 86
<> 144:ef7eb2e8f9f7 87 /* Prescaler enabled; set to 7 */
<> 144:ef7eb2e8f9f7 88 obj->adcReg->PRESCALE.WORD = ((True << ADC_PRESCALE_EN_BIT_POS) |
<> 144:ef7eb2e8f9f7 89 (7 << ADC_PRESCALE_VAL_BIT_POS)); /* ADC clock = 32MHz/(Prescale + 1) */
<> 144:ef7eb2e8f9f7 90
<> 144:ef7eb2e8f9f7 91 obj->adcReg->DELAY.WORD = ((0x34 << ADC_DELAY_SAMPLE_RATE_BIT_POS) | /** 25 uS Sets the sample rate in units of PCLKperiod * (Prescale + 1). */
<> 144:ef7eb2e8f9f7 92 (0x05 << ADC_DELAY_WARMUP_BIT_POS) | /** 12.5 uS Sets the measure time in units of PCLKperiod * (Prescale + 1). */
<> 144:ef7eb2e8f9f7 93 (0x1A << ADC_DELAY_SAMPLE_TIME_BIT_POS)); /** 2.5 uS Sets the warm-up time in units of PCLKperiod * (Prescale + 1). */
<> 144:ef7eb2e8f9f7 94
<> 144:ef7eb2e8f9f7 95 obj->adcReg->IR = 0; /** No interrupt generated */
<> 144:ef7eb2e8f9f7 96 } else {
<> 144:ef7eb2e8f9f7 97 obj->adcConf->convCh = adc_pin;
<> 144:ef7eb2e8f9f7 98
<> 144:ef7eb2e8f9f7 99 /* ADC register settings */
<> 144:ef7eb2e8f9f7 100 if((obj->adcConf->measurementType) == ADC_RELATIVE_MEAS) {
<> 144:ef7eb2e8f9f7 101 obj->adcReg->CONTROL.WORD = ((obj->adcConf->mode << ADC_CONTROL_MODE_BIT_POS) |
<> 144:ef7eb2e8f9f7 102 (obj->adcConf->measurementType << ADC_CONTROL_MEASTYPE_BIT_POS) |
<> 144:ef7eb2e8f9f7 103 (obj->adcConf->inputScale << ADC_CONTROL_INPUTSCALE_BIT_POS) |
<> 144:ef7eb2e8f9f7 104 (obj->adcConf->convCh << ADC_CONTROL_MEAS_CH_BIT_POS) |
<> 144:ef7eb2e8f9f7 105 (obj->adcConf->referenceCh << ADC_CONTROL_REF_CH_BIT_POS));
<> 144:ef7eb2e8f9f7 106 } else {
<> 144:ef7eb2e8f9f7 107 obj->adcReg->CONTROL.WORD = ((obj->adcConf->mode << ADC_CONTROL_MODE_BIT_POS) |
<> 144:ef7eb2e8f9f7 108 (obj->adcConf->measurementType << ADC_CONTROL_MEASTYPE_BIT_POS) |
<> 144:ef7eb2e8f9f7 109 (obj->adcConf->inputScale << ADC_CONTROL_INPUTSCALE_BIT_POS) |
<> 144:ef7eb2e8f9f7 110 (obj->adcConf->convCh << ADC_CONTROL_MEAS_CH_BIT_POS));
<> 144:ef7eb2e8f9f7 111 }
<> 144:ef7eb2e8f9f7 112
<> 144:ef7eb2e8f9f7 113 obj->adcReg->PRESCALE.WORD = ((True << ADC_PRESCALE_EN_BIT_POS) |
<> 144:ef7eb2e8f9f7 114 (obj->adcConf->PrescaleVal << ADC_PRESCALE_VAL_BIT_POS)); /* ADC clock = 32MHz/(Prescale + 1) */
<> 144:ef7eb2e8f9f7 115
<> 144:ef7eb2e8f9f7 116 obj->adcReg->DELAY.WORD = ((obj->adcConf->samplingRate << ADC_DELAY_SAMPLE_RATE_BIT_POS) | /** 25 uS Sets the sample rate in units of PCLKperiod * (Prescale + 1). */
<> 144:ef7eb2e8f9f7 117 (obj->adcConf->WarmUpTime << ADC_DELAY_WARMUP_BIT_POS) | /** 12.5 uS Sets the measure time in units of PCLKperiod * (Prescale + 1). */
<> 144:ef7eb2e8f9f7 118 (obj->adcConf->samplingTime << ADC_DELAY_SAMPLE_TIME_BIT_POS)); /** 2.5 uS Sets the warm-up time in units of PCLKperiod * (Prescale + 1). */
<> 144:ef7eb2e8f9f7 119
<> 144:ef7eb2e8f9f7 120 obj->adcReg->IR = obj->adcConf->interruptConfig; /** Interrupt setting */
<> 144:ef7eb2e8f9f7 121 }
<> 144:ef7eb2e8f9f7 122
<> 144:ef7eb2e8f9f7 123 /* Enable interrupt */
<> 144:ef7eb2e8f9f7 124 NVIC_ClearPendingIRQ(Adc_IRQn);
<> 144:ef7eb2e8f9f7 125 NVIC_EnableIRQ(Adc_IRQn);
<> 144:ef7eb2e8f9f7 126 }
<> 144:ef7eb2e8f9f7 127
<> 144:ef7eb2e8f9f7 128 /** Read the input voltage, represented as a float in the range [0.0, 1.0]
<> 144:ef7eb2e8f9f7 129 *
<> 144:ef7eb2e8f9f7 130 * @param obj The analogin object
<> 144:ef7eb2e8f9f7 131 * @return A floating value representing the current input voltage
<> 144:ef7eb2e8f9f7 132 */
<> 144:ef7eb2e8f9f7 133 float analogin_read(analogin_t *obj)
<> 144:ef7eb2e8f9f7 134 {
<> 144:ef7eb2e8f9f7 135 float retVal = 0.0;
<> 144:ef7eb2e8f9f7 136 uint16_t value = analogin_read_u16(obj);
<> 144:ef7eb2e8f9f7 137 retVal = (float)value * (1.0f / (float)0x03FF);
<> 144:ef7eb2e8f9f7 138 return(retVal);
<> 144:ef7eb2e8f9f7 139 }
<> 144:ef7eb2e8f9f7 140
<> 144:ef7eb2e8f9f7 141 /** Read the value from analogin pin, represented as an unsigned 16bit value
<> 144:ef7eb2e8f9f7 142 *
<> 144:ef7eb2e8f9f7 143 * @param obj The analogin object
<> 144:ef7eb2e8f9f7 144 * @return An unsigned 16bit value representing the current input voltage
<> 144:ef7eb2e8f9f7 145 */
<> 144:ef7eb2e8f9f7 146 uint16_t analogin_read_u16(analogin_t *obj)
<> 144:ef7eb2e8f9f7 147 {
<> 144:ef7eb2e8f9f7 148 uint16_t adcData = 0;
<> 144:ef7eb2e8f9f7 149 uint8_t adc_pin = 0;
<> 144:ef7eb2e8f9f7 150
<> 144:ef7eb2e8f9f7 151 CLOCK_ENABLE(CLOCK_ADC);
<> 144:ef7eb2e8f9f7 152
<> 144:ef7eb2e8f9f7 153 if (obj->pinFlag) {
<> 144:ef7eb2e8f9f7 154 switch (obj->pin) {
<> 144:ef7eb2e8f9f7 155 case A0:
<> 144:ef7eb2e8f9f7 156 adc_pin=0;
<> 144:ef7eb2e8f9f7 157 break;
<> 144:ef7eb2e8f9f7 158 case A1:
<> 144:ef7eb2e8f9f7 159 adc_pin = 1;
<> 144:ef7eb2e8f9f7 160 break;
<> 144:ef7eb2e8f9f7 161 case A2:
<> 144:ef7eb2e8f9f7 162 adc_pin = 2;
<> 144:ef7eb2e8f9f7 163 break;
<> 144:ef7eb2e8f9f7 164 case A3:
<> 144:ef7eb2e8f9f7 165 adc_pin = 3;
<> 144:ef7eb2e8f9f7 166 break;
<> 144:ef7eb2e8f9f7 167 default:
<> 144:ef7eb2e8f9f7 168 break;
<> 144:ef7eb2e8f9f7 169 }
<> 144:ef7eb2e8f9f7 170
<> 144:ef7eb2e8f9f7 171 /* Re initialize the pin configured for ADC read */
<> 144:ef7eb2e8f9f7 172 obj->adcReg->CONTROL.BITS.CONV_CH = adc_pin;
<> 144:ef7eb2e8f9f7 173 }
<> 144:ef7eb2e8f9f7 174
<> 144:ef7eb2e8f9f7 175 obj->adcReg->CONTROL.BITS.START_CONV=1; /* Start The Conversion */
<> 144:ef7eb2e8f9f7 176
<> 144:ef7eb2e8f9f7 177 while((uint32_t)(obj->adcReg->STATUS)!=(uint32_t)1) {
<> 144:ef7eb2e8f9f7 178 }
<> 144:ef7eb2e8f9f7 179 adcData =(uint16_t)(obj->adcReg->DATA);
<> 144:ef7eb2e8f9f7 180 CLOCK_DISABLE(CLOCK_ADC);
<> 144:ef7eb2e8f9f7 181
<> 144:ef7eb2e8f9f7 182 return(adcData);
<> 144:ef7eb2e8f9f7 183 }
<> 144:ef7eb2e8f9f7 184
<> 144:ef7eb2e8f9f7 185 #endif // DEVICE_ANALOGIN
<> 144:ef7eb2e8f9f7 186