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Diff: targets/TARGET_Freescale/TARGET_KLXX/analogin_api.c
- Revision:
- 149:156823d33999
- Parent:
- 144:ef7eb2e8f9f7
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/targets/TARGET_Freescale/TARGET_KLXX/analogin_api.c Fri Oct 28 11:17:30 2016 +0100 @@ -0,0 +1,87 @@ +/* mbed Microcontroller Library + * Copyright (c) 2006-2013 ARM Limited + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ +#include "mbed_assert.h" +#include "analogin_api.h" + +#include "cmsis.h" +#include "pinmap.h" +#include "clk_freqs.h" +#include "PeripheralPins.h" + +#define MAX_FADC 6000000 +#define CHANNELS_A_SHIFT 5 + + +void analogin_init(analogin_t *obj, PinName pin) { + obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC); + MBED_ASSERT(obj->adc != (ADCName)NC); + + SIM->SCGC6 |= SIM_SCGC6_ADC0_MASK; + + uint32_t port = (uint32_t)pin >> PORT_SHIFT; + SIM->SCGC5 |= 1 << (SIM_SCGC5_PORTA_SHIFT + port); + + uint32_t cfg2_muxsel = ADC_CFG2_MUXSEL_MASK; + if (obj->adc & (1 << CHANNELS_A_SHIFT)) { + cfg2_muxsel = 0; + } + + // bus clk + uint32_t PCLK = bus_frequency(); + uint32_t clkdiv; + for (clkdiv = 0; clkdiv < 4; clkdiv++) { + if ((PCLK >> clkdiv) <= MAX_FADC) + break; + } + if (clkdiv == 4) //Set max div + clkdiv = 0x7; + + ADC0->SC1[1] = ADC_SC1_ADCH(obj->adc & ~(1 << CHANNELS_A_SHIFT)); + + ADC0->CFG1 = ADC_CFG1_ADLPC_MASK // Low-Power Configuration + | ADC_CFG1_ADIV(clkdiv & 0x3) // Clock Divide Select: (Input Clock)/8 + | ADC_CFG1_ADLSMP_MASK // Long Sample Time + | ADC_CFG1_MODE(3) // (16)bits Resolution + | ADC_CFG1_ADICLK(clkdiv >> 2); // Input Clock: (Bus Clock)/2 + + ADC0->CFG2 = cfg2_muxsel // ADxxb or ADxxa channels + | ADC_CFG2_ADHSC_MASK // High-Speed Configuration + | ADC_CFG2_ADLSTS(0); // Long Sample Time Select + + ADC0->SC2 = ADC_SC2_REFSEL(0); // Default Voltage Reference + + ADC0->SC3 = ADC_SC3_AVGE_MASK // Hardware Average Enable + | ADC_SC3_AVGS(0); // 4 Samples Averaged + + pinmap_pinout(pin, PinMap_ADC); +} + +uint16_t analogin_read_u16(analogin_t *obj) { + // start conversion + ADC0->SC1[0] = ADC_SC1_ADCH(obj->adc & ~(1 << CHANNELS_A_SHIFT)); + + // Wait Conversion Complete + while ((ADC0->SC1[0] & ADC_SC1_COCO_MASK) != ADC_SC1_COCO_MASK); + + // Return value + return (uint16_t)ADC0->R[0]; +} + +float analogin_read(analogin_t *obj) { + uint16_t value = analogin_read_u16(obj); + return (float)value * (1.0f / (float)0xFFFF); +} +