/* 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" #if DEVICE_ANALOGIN #include "cmsis.h" #include "pinmap.h" #include "PeripheralNames.h" #include "fsl_adc16.h" #include "PeripheralPins.h" /* Array of ADC peripheral base address. */ static ADC_Type *const adc_addrs[] = ADC_BASE_PTRS; #define MAX_FADC 6000000 void analogin_init(analogin_t *obj, PinName pin) { obj->adc = (ADCName)pinmap_peripheral(pin, PinMap_ADC); MBED_ASSERT(obj->adc != (ADCName)NC); uint32_t instance = obj->adc >> ADC_INSTANCE_SHIFT; uint32_t bus_clock; adc16_config_t adc16_config; bus_clock = CLOCK_GetFreq(kCLOCK_BusClk); uint32_t clkdiv; for (clkdiv = 0; clkdiv < 4; clkdiv++) { if ((bus_clock >> clkdiv) <= MAX_FADC) break; } if (clkdiv == 4) { clkdiv = 0x3; //Set max div } ADC16_GetDefaultConfig(&adc16_config); adc16_config.clockSource = kADC16_ClockSourceAlt0; adc16_config.clockDivider = (adc16_clock_divider_t)clkdiv; adc16_config.resolution = kADC16_ResolutionSE16Bit; ADC16_Init(adc_addrs[instance], &adc16_config); ADC16_EnableHardwareTrigger(adc_addrs[instance], false); ADC16_SetHardwareAverage(adc_addrs[instance], kADC16_HardwareAverageCount4); pinmap_pinout(pin, PinMap_ADC); } uint16_t analogin_read_u16(analogin_t *obj) { uint32_t instance = obj->adc >> ADC_INSTANCE_SHIFT; adc16_channel_config_t adc16_channel_config; adc16_channel_config.channelNumber = obj->adc & 0xF; adc16_channel_config.enableInterruptOnConversionCompleted = false; #if defined(FSL_FEATURE_ADC16_HAS_DIFF_MODE) && FSL_FEATURE_ADC16_HAS_DIFF_MODE adc16_channel_config.enableDifferentialConversion = false; #endif ADC16_SetChannelMuxMode(adc_addrs[instance], obj->adc & (1 << ADC_B_CHANNEL_SHIFT) ? kADC16_ChannelMuxB : kADC16_ChannelMuxA); /* * When in software trigger mode, each conversion would be launched once calling the "ADC16_ChannelConfigure()" * function, which works like writing a conversion command and executing it. */ ADC16_SetChannelConfig(adc_addrs[instance], 0, &adc16_channel_config); while (0U == (kADC16_ChannelConversionDoneFlag & ADC16_GetChannelStatusFlags(adc_addrs[instance], 0))) { } return ADC16_GetChannelConversionValue(adc_addrs[instance], 0); } float analogin_read(analogin_t *obj) { uint16_t value = analogin_read_u16(obj); return (float)value * (1.0f / (float)0xFFFF); } #endif