circuitpython/ports/mimxrt10xx/common-hal/analogio/AnalogIn.c
2022-05-24 08:44:09 -07:00

91 lines
2.9 KiB
C

/*
* This file is part of the MicroPython project, http://micropython.org/
*
* The MIT License (MIT)
*
* Copyright (c) 2016 Scott Shawcroft for Adafruit Industries
* Copyright (c) 2019 Artur Pacholec
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in
* all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
* THE SOFTWARE.
*/
#include "common-hal/analogio/AnalogIn.h"
#include "shared-bindings/analogio/AnalogIn.h"
#include "shared-bindings/microcontroller/Pin.h"
#include <string.h>
#include "py/runtime.h"
#include "fsl_adc.h"
#define ADC_CHANNEL_GROUP 0
void common_hal_analogio_analogin_construct(analogio_analogin_obj_t *self,
const mcu_pin_obj_t *pin) {
adc_config_t config = {0};
if (pin->adc == NULL) {
raise_ValueError_invalid_pin();
}
ADC_GetDefaultConfig(&config);
config.enableLongSample = true;
config.samplePeriodMode = kADC_SamplePeriod8or24Clocks;
ADC_Init(pin->adc, &config);
ADC_SetHardwareAverageConfig(pin->adc, kADC_HardwareAverageCount32);
ADC_DoAutoCalibration(pin->adc);
claim_pin(pin);
self->pin = pin;
}
bool common_hal_analogio_analogin_deinited(analogio_analogin_obj_t *self) {
return self->pin == NULL;
}
void common_hal_analogio_analogin_deinit(analogio_analogin_obj_t *self) {
if (common_hal_analogio_analogin_deinited(self)) {
return;
}
common_hal_reset_pin(self->pin);
self->pin = NULL;
}
uint16_t common_hal_analogio_analogin_get_value(analogio_analogin_obj_t *self) {
adc_channel_config_t config = { 0 };
config.channelNumber = self->pin->adc_channel;
ADC_SetChannelConfig(self->pin->adc, ADC_CHANNEL_GROUP, &config);
while (!ADC_GetChannelStatusFlags(self->pin->adc, ADC_CHANNEL_GROUP)) {
}
// Stretch 12-bit ADC reading to 16 bits via 24-bit interim result
return (ADC_GetChannelConversionValue(self->pin->adc, ADC_CHANNEL_GROUP) * 0x1001) >> 8;
}
float common_hal_analogio_analogin_get_reference_voltage(analogio_analogin_obj_t *self) {
return 3.3f;
}