118 lines
3.3 KiB
C
118 lines
3.3 KiB
C
/**
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* Driver for AD7705/AD7706 SPI ADC
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*
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* Part of esp-open-rtos
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* Copyright (C) 2017 Ruslan V. Uss <unclerus@gmail.com>
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* BSD Licensed as described in the file LICENSE
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*/
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#ifndef _EXTRAS_AD770X_H_
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#define _EXTRAS_AD770X_H_
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#include <stdint.h>
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#include <stdbool.h>
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#ifdef __cplusplus
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extern "C" {
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#endif
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/**
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* Input gain
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*/
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typedef enum
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{
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AD770X_GAIN_1 = 0,
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AD770X_GAIN_2,
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AD770X_GAIN_4,
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AD770X_GAIN_8,
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AD770X_GAIN_16,
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AD770X_GAIN_32,
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AD770X_GAIN_64,
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AD770X_GAIN_128
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} ad770x_gain_t;
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/**
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* Master clock frequency
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*/
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typedef enum
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{
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AD770X_MCLK_1MHz = 0, //!< 1 MHz
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AD770X_MCLK_2MHz, //!< 2 MHz
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AD770X_MCLK_2_4576MHz, //!< 2.4576 MHz
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AD770X_MCLK_4_9152MHz, //!< 4.9152 MHz
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} ad770x_master_clock_t;
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/**
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* Output update rate
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*/
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typedef enum
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{
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AD770X_RATE_20 = 0, //!< Output update rate is 20 Hz, -3 dB filter cutoff = 5.24 Hz, works with 1 or 2 MHz master clock
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AD770X_RATE_25, //!< Output update rate is 25 Hz, -3 dB filter cutoff = 6.55 Hz, works with 1 or 2 MHz master clock
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AD770X_RATE_100, //!< Output update rate is 100 Hz, -3 dB filter cutoff = 26.2 Hz, works with 1 or 2 MHz master clock
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AD770X_RATE_200, //!< Output update rate is 200 Hz, -3 dB filter cutoff = 52.4 Hz, works with 1 or 2 MHz master clock
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AD770X_RATE_50, //!< Output update rate is 50 Hz, -3 dB filter cutoff = 13.1 Hz, works with 2.4576 or 4.9152 MHz master clock
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AD770X_RATE_60, //!< Output update rate is 60 Hz, -3 dB filter cutoff = 15.7 Hz, works with 2.4576 or 4.9152 MHz master clock
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AD770X_RATE_250, //!< Output update rate is 250 Hz, -3 dB filter cutoff = 65.5 Hz, works with 2.4576 or 4.9152 MHz master clock
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AD770X_RATE_500, //!< Output update rate is 500 Hz, -3 dB filter cutoff = 131 Hz, works with 2.4576 or 4.9152 MHz master clock
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} ad770x_update_rate_t;
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/**
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* Device mode
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*/
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typedef enum
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{
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AD770X_MODE_NORMAL = 0,
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AD770X_MODE_CALIBRATION,
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AD770X_MODE_ZERO_CALIBRATION,
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AD770X_MODE_FULL_CALIBRATION
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} ad770x_mode_t;
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/**
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* Device descriptor
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*/
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typedef struct
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{
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uint8_t cs_pin; //!< GPIO pin for chip select
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ad770x_master_clock_t master_clock; //!< Master clock frequency
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bool bipolar; //!< Bipolar/Unipolar mode
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ad770x_gain_t gain; //!< Input gain
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ad770x_update_rate_t update_rate; //!< Output update rate
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} ad770x_params_t;
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/**
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* Init device and setup channel params
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* @param params Device descriptor pointer
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* @param channel Input channel
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* @return Non-zero when error occured
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*/
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int ad770x_init(const ad770x_params_t *params, uint8_t channel);
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/**
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* Set device mode (see datasheet)
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* @param params Device descriptor pointer
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* @param channel Input channel
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* @param mode Device mode
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*/
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void ad770x_set_mode(const ad770x_params_t *params, uint8_t channel, ad770x_mode_t mode);
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/**
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* Get conversion status
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* @param params Device descriptor pointer
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* @param channel Input channel
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* @return true when data is ready
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*/
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bool ad770x_data_ready(const ad770x_params_t *params, uint8_t channel);
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/**
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* Get converted ADC value
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* @param params Device descriptor pointer
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* @param channel Input channel
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* @return Raw ADC value
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*/
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uint16_t ad770x_raw_adc_value(const ad770x_params_t *params, uint8_t channel);
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#ifdef __cplusplus
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}
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#endif
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#endif /* _EXTRAS_AD770X_H_ */
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