764 lines
19 KiB
C++
764 lines
19 KiB
C++
//ADS1256 cpp file
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/*
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Name: ADS1256.cpp
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Created: 2022/07/14
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Author: Curious Scientist
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Editor: Notepad++
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Comment: Visit https://curiousscientist.tech/blog/ADS1256-custom-library
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Special thanks to:
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Abraão Queiroz for spending time on the code and suggesting corrections for ESP32 microcontrollers
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Benjamin Pelletier for pointing out and fixing an issue around the handling of the DRDY signal
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RadoMmm for suggesting an improvement on the ADC-to-Volts conversion
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*/
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#include "Arduino.h"
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#include "ADS1256.h"
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#include "SPI.h"
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#define convertSigned24BitToLong(value) ((value) & (1l << 23) ? (value) - 0x1000000 : value)
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//Constructor
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ADS1256::ADS1256(const int8_t DRDY_pin, const int8_t RESET_pin, const int8_t SYNC_pin, const int8_t CS_pin,float VREF, SPIClass* spi): _spi(spi),
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_DRDY_pin(DRDY_pin), _RESET_pin(RESET_pin), _SYNC_pin(SYNC_pin), _CS_pin(CS_pin), _VREF(VREF), _PGA(0)
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{
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pinMode(_DRDY_pin, INPUT);
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if(RESET_pin != PIN_UNUSED)
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{
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pinMode(_RESET_pin, OUTPUT);
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}
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if(SYNC_pin != PIN_UNUSED)
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{
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pinMode(_SYNC_pin, OUTPUT);
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}
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if(CS_pin != PIN_UNUSED)
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{
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pinMode(_CS_pin, OUTPUT);
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}
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updateConversionParameter();
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}
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//Initialization
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void ADS1256::InitializeADC()
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{
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//Chip select LOW
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CS_LOW();
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//We do a manual chip reset on the ADS1256 - Datasheet Page 27/ RESET
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if(_RESET_pin != PIN_UNUSED)
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{
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digitalWrite(_RESET_pin, LOW);
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delay(200);
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digitalWrite(_RESET_pin, HIGH); //RESET is set to high
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delay(1000);
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}
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//Sync pin is also treated if it is defined
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if(_SYNC_pin != PIN_UNUSED)
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{
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digitalWrite(_SYNC_pin, HIGH); //RESET is set to high
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}
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#ifndef ADS1256_SPI_ALREADY_STARTED //Guard macro to allow external initialization of the SPI
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_spi->begin();
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#endif
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//Applying arbitrary default values to speed up the starting procedure if the user just want to get quick readouts
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//We both pass values to the variables and then send those values to the corresponding registers
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delay(200);
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_STATUS = 0b00110110; //BUFEN and ACAL enabled, Order is MSB, rest is read only
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writeRegister(STATUS_REG, _STATUS);
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delay(200);
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_MUX = 0b00000001; //MUX AIN0+AIN1
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writeRegister(MUX_REG, _MUX);
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delay(200);
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_ADCON = 0b00000000; //ADCON - CLK: OFF, SDCS: OFF, PGA = 0 (+/- 5 V)
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writeRegister(ADCON_REG, _ADCON);
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delay(200);
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updateConversionParameter();
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_DRATE = 0b10000010; //100SPS
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writeRegister(DRATE_REG, _DRATE);
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delay(200);
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sendDirectCommand(0b11110000); //Offset and self-gain calibration
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delay(200);
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_isAcquisitionRunning = false; //MCU will be waiting to start a continuous acquisition
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}
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void ADS1256::waitForLowDRDY()
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{
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while (digitalRead(_DRDY_pin) == HIGH) {}
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}
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void ADS1256::waitForHighDRDY()
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{
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#if F_CPU >= 48000000 //Fast MCUs need this protection to wait until DRDY goes high after a conversion
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while (digitalRead(_DRDY_pin) == LOW) {}
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#endif
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}
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void ADS1256::stopConversion() //Sending SDATAC to stop the continuous conversion
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{
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waitForLowDRDY(); //SDATAC should be called after DRDY goes LOW (p35. Figure 33)
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_spi->transfer(0b00001111); //Send SDATAC to the ADC
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CS_HIGH(); //We finished the command sequence, so we switch it back to HIGH
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_spi->endTransaction();
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_isAcquisitionRunning = false; //Reset to false, so the MCU will be able to start a new conversion
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}
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void ADS1256::setDRATE(uint8_t drate) //Setting DRATE (sampling frequency)
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{
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writeRegister(DRATE_REG, drate);
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_DRATE = drate;
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delayMicroseconds(500);
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}
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void ADS1256::setMUX(uint8_t mux) //Setting MUX (input channel)
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{
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writeRegister(MUX_REG, mux);
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_MUX = mux;
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//delayMicroseconds(500);
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}
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void ADS1256::setPGA(uint8_t pga) //Setting PGA (input voltage range)
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{
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_PGA = pga;
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_ADCON = readRegister(ADCON_REG); //Read the most recent value of the register
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_ADCON = (_ADCON & 0b11111000) | (_PGA & 0b00000111); // Clearing and then setting bits 2-0 based on pga
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writeRegister(ADCON_REG, _ADCON);
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delayMicroseconds(1000); //Delay to allow the PGA to settle after changing its value
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updateConversionParameter(); //Update the multiplier according top the new PGA value
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}
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uint8_t ADS1256::getPGA() //Reading PGA from the ADCON register
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{
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uint8_t pgaValue = readRegister(ADCON_REG) & 0b00000111;
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//Reading the ADCON_REG and keeping the first three bits.
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return(pgaValue);
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}
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void ADS1256::setCLKOUT(uint8_t clkout) //Setting CLKOUT
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{
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_ADCON = readRegister(ADCON_REG); //Read the most recent value of the register
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//Values: 0, 1, 2, 3
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if(clkout == 0)
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{
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//00
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bitWrite(_ADCON, 6, 0);
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bitWrite(_ADCON, 5, 0);
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}
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else if(clkout == 1)
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{
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//01 (default)
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bitWrite(_ADCON, 6, 0);
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bitWrite(_ADCON, 5, 1);
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}
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else if(clkout == 2)
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{
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//10
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bitWrite(_ADCON, 6, 1);
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bitWrite(_ADCON, 5, 0);
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}
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else if(clkout == 3)
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{
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//11
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bitWrite(_ADCON, 6, 1);
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bitWrite(_ADCON, 5, 1);
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}
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else{}
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writeRegister(ADCON_REG, _ADCON);
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delay(100);
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}
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void ADS1256::setSDCS(uint8_t sdcs) //Setting SDCS
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{
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_ADCON = readRegister(ADCON_REG); //Read the most recent value of the register
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//Values: 0, 1, 2, 3
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if(sdcs == 0)
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{
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//00 (default)
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bitWrite(_ADCON, 4, 0);
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bitWrite(_ADCON, 3, 0);
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}
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else if(sdcs == 1)
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{
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//01
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bitWrite(_ADCON, 4, 0);
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bitWrite(_ADCON, 3, 1);
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}
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else if(sdcs == 2)
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{
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//10
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bitWrite(_ADCON, 4, 1);
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bitWrite(_ADCON, 3, 0);
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}
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else if(sdcs == 3)
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{
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//11
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bitWrite(_ADCON, 4, 1);
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bitWrite(_ADCON, 3, 1);
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}
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else{}
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writeRegister(ADCON_REG, _ADCON);
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delay(100);
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}
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void ADS1256::setByteOrder(uint8_t byteOrder) //Setting byte order (MSB/LSB)
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{
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_STATUS = readRegister(STATUS_REG); //Read the most recent value of the register
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if(byteOrder == 0)
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{
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//Byte order is MSB (default)
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bitWrite(_STATUS, 3, 0);
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//Set value of _STATUS at the third bit to 0
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}
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else if(byteOrder == 1)
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{
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//Byte order is LSB
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bitWrite(_STATUS, 3, 1);
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//Set value of _STATUS at the third bit to 1
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}
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else{}
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writeRegister(STATUS_REG, _STATUS);
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delay(100);
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}
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uint8_t ADS1256::getByteOrder() //Getting byte order (MSB/LSB)
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{
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uint8_t statusValue = readRegister(STATUS_REG); //Read the whole STATUS register
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return bitRead(statusValue, 3);
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}
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void ADS1256::setAutoCal(uint8_t acal) //Setting ACAL (Automatic SYSCAL)
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{
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_STATUS = readRegister(STATUS_REG); //Read the most recent value of the register
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if(acal == 0)
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{
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//Auto-calibration is disabled (default)
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bitWrite(_STATUS, 2, 0);
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//_STATUS |= B00000000;
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}
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else if(acal == 1)
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{
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//Auto-calibration is enabled
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bitWrite(_STATUS, 2, 1);
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//_STATUS |= B00000100;
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}
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else{}
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writeRegister(STATUS_REG, _STATUS);
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delay(100);
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}
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uint8_t ADS1256::getAutoCal() //Getting ACAL (Automatic SYSCAL)
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{
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uint8_t statusValue = readRegister(STATUS_REG); //Read the whole STATUS register
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return bitRead(statusValue, 2);
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}
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void ADS1256::setBuffer(uint8_t bufen) //Setting input buffer (Input impedance)
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{
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_STATUS = readRegister(STATUS_REG); //Read the most recent value of the register
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if(bufen == 0)
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{
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//Analog input buffer is disabled (default)
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//_STATUS |= B00000000;
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bitWrite(_STATUS, 1, 0);
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}
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else if(bufen == 1)
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{
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//Analog input buffer is enabled (recommended)
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//_STATUS |= B00000010;
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bitWrite(_STATUS, 1, 1);
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}
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else{}
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writeRegister(STATUS_REG, _STATUS);
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delay(100);
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}
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uint8_t ADS1256::getBuffer() //Getting input buffer (Input impedance)
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{
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uint8_t statusValue = readRegister(STATUS_REG); //Read the whole STATUS register
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return bitRead(statusValue, 1);
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}
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void ADS1256::setGPIO(uint8_t dir0, uint8_t dir1, uint8_t dir2, uint8_t dir3) //Setting GPIO
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{
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_GPIO = readRegister(IO_REG); //Read the most recent value of the register
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//Default: 11100000 - DEC: 224 - Ref: p32 I/O section
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//Sets D3-D0 as input or output
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uint8_t GPIO_bit7, GPIO_bit6, GPIO_bit5, GPIO_bit4;
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//Bit7: DIR3
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if(dir3 == 1)
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{
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GPIO_bit7 = 1; //D3 is input (default)
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}
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else
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{
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GPIO_bit7 = 0; //D3 is output
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}
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bitWrite(_GPIO, 7, GPIO_bit7);
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//-----------------------------------------------------
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//Bit6: DIR2
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if(dir2 == 1)
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{
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GPIO_bit6 = 1; //D2 is input (default)
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}
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else
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{
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GPIO_bit6 = 0; //D2 is output
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}
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bitWrite(_GPIO, 6, GPIO_bit6);
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//-----------------------------------------------------
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//Bit5: DIR1
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if(dir1 == 1)
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{
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GPIO_bit5 = 1; //D1 is input (default)
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}
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else
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{
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GPIO_bit5 = 0; //D1 is output
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}
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bitWrite(_GPIO, 5, GPIO_bit5);
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//-----------------------------------------------------
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//Bit4: DIR0
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if(dir0 == 1)
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{
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GPIO_bit4 = 1; //D0 is input
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}
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else
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{
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GPIO_bit4 = 0; //D0 is output (default)
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}
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bitWrite(_GPIO, 4, GPIO_bit4);
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//-----------------------------------------------------
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writeRegister(IO_REG, _GPIO);
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delay(100);
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}
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void ADS1256::writeGPIO(uint8_t dir0value, uint8_t dir1value, uint8_t dir2value, uint8_t dir3value) //Writing GPIO
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{
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_GPIO = readRegister(IO_REG);
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//Sets D3-D0 output values
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//It is important that first one must use setGPIO, then writeGPIO
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uint8_t GPIO_bit3, GPIO_bit2, GPIO_bit1, GPIO_bit0;
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//Bit3: DIR3
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if(dir3value == 1)
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{
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GPIO_bit3 = 1;
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}
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else
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{
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GPIO_bit3 = 0;
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}
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bitWrite(_GPIO, 3, GPIO_bit3);
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//-----------------------------------------------------
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//Bit2: DIR2
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if(dir2value == 1)
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{
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GPIO_bit2 = 1;
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}
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else
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{
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GPIO_bit2 = 0;
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}
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bitWrite(_GPIO, 2, GPIO_bit2);
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//-----------------------------------------------------
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//Bit1: DIR1
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if(dir1value == 1)
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{
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GPIO_bit1 = 1;
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}
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else
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{
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GPIO_bit1 = 0;
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}
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bitWrite(_GPIO, 1, GPIO_bit1);
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//-----------------------------------------------------
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//Bit0: DIR0
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if(dir0value == 1)
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{
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GPIO_bit0 = 1;
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}
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else
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{
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GPIO_bit0 = 0;
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}
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bitWrite(_GPIO, 0, GPIO_bit0);
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//-----------------------------------------------------
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writeRegister(IO_REG, _GPIO);
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delay(100);
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}
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uint8_t ADS1256::readGPIO(uint8_t gpioPin) //Reading GPIO
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{
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uint8_t GPIO_bit3, GPIO_bit2, GPIO_bit1, GPIO_bit0, GPIO_return;
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_GPIO = readRegister(IO_REG); //Read the GPIO register
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//Save each bit values in a variable
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GPIO_bit3 = bitRead(_GPIO, 3);
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GPIO_bit2 = bitRead(_GPIO, 2);
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GPIO_bit1 = bitRead(_GPIO, 1);
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GPIO_bit0 = bitRead(_GPIO, 0);
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delay(100);
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switch(gpioPin) //Selecting which value should be returned
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{
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case 0:
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GPIO_return = GPIO_bit0;
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break;
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case 1:
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GPIO_return = GPIO_bit1;
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break;
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case 2:
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GPIO_return = GPIO_bit2;
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break;
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case 3:
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GPIO_return = GPIO_bit3;
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break;
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}
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return GPIO_return;
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}
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void ADS1256::sendDirectCommand(uint8_t directCommand)
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{
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//Direct commands can be found in the datasheet Page 34, Table 24.
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_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
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CS_LOW(); //REF: P34: "CS must stay low during the entire command sequence"
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delayMicroseconds(5);
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_spi->transfer(directCommand); //Send Command
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delayMicroseconds(5);
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CS_HIGH(); //REF: P34: "CS must stay low during the entire command sequence"
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_spi->endTransaction();
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}
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float ADS1256::convertToVoltage(int32_t rawData) //Converting the 24-bit data into a voltage value
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{
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return(conversionParameter * rawData);
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}
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void ADS1256::writeRegister(uint8_t registerAddress, uint8_t registerValueToWrite)
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{
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waitForLowDRDY();
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_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
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//SPI_MODE1 = output edge: rising, data capture: falling; clock polarity: 0, clock phase: 1.
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CS_LOW(); //CS must stay LOW during the entire sequence [Ref: P34, T24]
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delayMicroseconds(5); //see t6 in the datasheet
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_spi->transfer(0x50 | registerAddress); // 0x50 = 01010000 = WREG
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_spi->transfer(0x00); //2nd (empty) command byte
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_spi->transfer(registerValueToWrite); //pass the value to the register
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CS_HIGH();
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_spi->endTransaction();
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}
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long ADS1256::readRegister(uint8_t registerAddress) //Reading a register
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{
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waitForLowDRDY();
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_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
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//SPI_MODE1 = output edge: rising, data capture: falling; clock polarity: 0, clock phase: 1.
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CS_LOW(); //CS must stay LOW during the entire sequence [Ref: P34, T24]
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_spi->transfer(0x10 | registerAddress); //0x10 = 0001000 = RREG - OR together the two numbers (command + address)
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_spi->transfer(0x00); //2nd (empty) command byte
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delayMicroseconds(5); //see t6 in the datasheet
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uint8_t regValue = _spi->transfer(0xFF); //read out the register value
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CS_HIGH();
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_spi->endTransaction();
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return regValue;
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}
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long ADS1256::readSingle() //Reading a single value ONCE using the RDATA command
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{
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_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
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CS_LOW(); //REF: P34: "CS must stay low during the entire command sequence"
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waitForLowDRDY();
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_spi->transfer(0b00000001); //Issue RDATA (0000 0001) command
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delayMicroseconds(7); //Wait t6 time (~6.51 us) REF: P34, FIG:30.
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_outputBuffer[0] = _spi->transfer(0); // MSB
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_outputBuffer[1] = _spi->transfer(0); // Mid-byte
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_outputBuffer[2] = _spi->transfer(0); // LSB
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//Shifting and combining the above three items into a single, 24-bit number
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_outputValue = ((long)_outputBuffer[0]<<16) | ((long)_outputBuffer[1]<<8) | (_outputBuffer[2]);
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_outputValue = convertSigned24BitToLong(_outputValue);
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CS_HIGH(); //We finished the command sequence, so we set CS to HIGH
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_spi->endTransaction();
|
|
|
|
return(_outputValue);
|
|
}
|
|
|
|
long ADS1256::readSingleContinuous() //Reads the recently selected input channel using RDATAC
|
|
{
|
|
if(_isAcquisitionRunning == false)
|
|
{
|
|
_isAcquisitionRunning = true;
|
|
_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
|
|
CS_LOW(); //REF: P34: "CS must stay low during the entire command sequence"
|
|
waitForLowDRDY();
|
|
_spi->transfer(0b00000011); //Issue RDATAC (0000 0011)
|
|
delayMicroseconds(7); //Wait t6 time (~6.51 us) REF: P34, FIG:30.
|
|
}
|
|
else
|
|
{
|
|
waitForLowDRDY();
|
|
}
|
|
|
|
_outputBuffer[0] = _spi->transfer(0); // MSB
|
|
_outputBuffer[1] = _spi->transfer(0); // Mid-byte
|
|
_outputBuffer[2] = _spi->transfer(0); // LSB
|
|
|
|
_outputValue = ((long)_outputBuffer[0]<<16) | ((long)_outputBuffer[1]<<8) | (_outputBuffer[2]);
|
|
_outputValue = convertSigned24BitToLong(_outputValue);
|
|
|
|
waitForHighDRDY();
|
|
|
|
return _outputValue;
|
|
}
|
|
|
|
long ADS1256::cycleSingle()
|
|
{
|
|
if(_isAcquisitionRunning == false)
|
|
{
|
|
_isAcquisitionRunning = true;
|
|
_cycle = 0;
|
|
_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
|
|
CS_LOW(); //CS must stay LOW during the entire sequence [Ref: P34, T24]
|
|
_spi->transfer(0x50 | 1); // 0x50 = WREG //1 = MUX
|
|
_spi->transfer(0x00);
|
|
_spi->transfer(SING_0); //AIN0+AINCOM
|
|
CS_HIGH();
|
|
delay(50);
|
|
CS_LOW(); //CS must stay LOW during the entire sequence [Ref: P34, T24]
|
|
}
|
|
else
|
|
{}
|
|
|
|
if(_cycle < 8)
|
|
{
|
|
_outputValue = 0;
|
|
waitForLowDRDY();
|
|
//Step 1. - Updating MUX
|
|
switch (_cycle)
|
|
{
|
|
//Channels are written manually
|
|
case 0: //Channel 2
|
|
updateMUX(SING_1); //AIN1+AINCOM
|
|
break;
|
|
|
|
case 1: //Channel 3
|
|
updateMUX(SING_2); //AIN2+AINCOM
|
|
break;
|
|
|
|
case 2: //Channel 4
|
|
updateMUX(SING_3); //AIN3+AINCOM
|
|
break;
|
|
|
|
case 3: //Channel 5
|
|
updateMUX(SING_4); //AIN4+AINCOM
|
|
break;
|
|
|
|
case 4: //Channel 6
|
|
updateMUX(SING_5); //AIN5+AINCOM
|
|
break;
|
|
|
|
case 5: //Channel 7
|
|
updateMUX(SING_6); //AIN6+AINCOM
|
|
break;
|
|
|
|
case 6: //Channel 8
|
|
updateMUX(SING_7); //AIN7+AINCOM
|
|
break;
|
|
|
|
case 7: //Channel 1
|
|
updateMUX(SING_0); //AIN0+AINCOM
|
|
break;
|
|
}
|
|
//Step 2.
|
|
_spi->transfer(0b11111100); //SYNC
|
|
delayMicroseconds(4); //t11 delay 24*tau = 3.125 us //delay should be larger, so we delay by 4 us
|
|
_spi->transfer(0b11111111); //WAKEUP
|
|
|
|
//Step 3.
|
|
//Issue RDATA (0000 0001) command
|
|
_spi->transfer(0b00000001);
|
|
delayMicroseconds(7); //Wait t6 time (~6.51 us) REF: P34, FIG:30.
|
|
|
|
_outputBuffer[0] = _spi->transfer(0x0F); // MSB
|
|
_outputBuffer[1] = _spi->transfer(0x0F); // Mid-byte
|
|
_outputBuffer[2] = _spi->transfer(0x0F); // LSB
|
|
|
|
_outputValue = ((long)_outputBuffer[0]<<16) | ((long)_outputBuffer[1]<<8) | (_outputBuffer[2]);
|
|
_outputValue = convertSigned24BitToLong(_outputValue);
|
|
|
|
_cycle++; //Increase cycle - This will move to the next MUX input channel
|
|
if(_cycle == 8)
|
|
{
|
|
_cycle = 0; //Reset to 0 - Restart conversion from the 1st input channel
|
|
}
|
|
}
|
|
|
|
return _outputValue;
|
|
}
|
|
|
|
long ADS1256::cycleDifferential()
|
|
{
|
|
if(_isAcquisitionRunning == false)
|
|
{
|
|
_cycle = 0;
|
|
_isAcquisitionRunning = true;
|
|
_spi->beginTransaction(SPISettings(1920000, MSBFIRST, SPI_MODE1));
|
|
|
|
//Set the AIN0+AIN1 as inputs manually
|
|
CS_LOW(); //CS must stay LOW during the entire sequence [Ref: P34, T24]
|
|
_spi->transfer(0x50 | 1); // 0x50 = WREG //1 = MUX
|
|
_spi->transfer(0x00);
|
|
_spi->transfer(DIFF_0_1); //AIN0+AIN1
|
|
CS_HIGH();
|
|
delay(50);
|
|
CS_LOW(); //CS must stay LOW during the entire sequence [Ref: P34, T24]
|
|
}
|
|
else
|
|
{}
|
|
|
|
if(_cycle < 4)
|
|
{
|
|
_outputValue = 0;
|
|
//DRDY has to go low
|
|
waitForLowDRDY();
|
|
|
|
//Step 1. - Updating MUX
|
|
switch (_cycle)
|
|
{
|
|
case 0: //Channel 2
|
|
updateMUX(DIFF_2_3); //AIN2+AIN3
|
|
break;
|
|
|
|
case 1: //Channel 3
|
|
updateMUX(DIFF_4_5); //AIN4+AIN5
|
|
break;
|
|
|
|
case 2: //Channel 4
|
|
updateMUX(DIFF_6_7); //AIN6+AIN7
|
|
break;
|
|
|
|
case 3: //Channel 1
|
|
updateMUX(DIFF_0_1); //AIN0+AIN1
|
|
break;
|
|
}
|
|
|
|
_spi->transfer(0b11111100); //SYNC
|
|
delayMicroseconds(4); //t11 delay 24*tau = 3.125 us //delay should be larger, so we delay by 4 us
|
|
_spi->transfer(0b11111111); //WAKEUP
|
|
|
|
//Step 3.
|
|
_spi->transfer(0b00000001); //Issue RDATA (0000 0001) command
|
|
delayMicroseconds(7); //Wait t6 time (~6.51 us) REF: P34, FIG:30.
|
|
|
|
_outputBuffer[0] = _spi->transfer(0); // MSB
|
|
_outputBuffer[1] = _spi->transfer(0); // Mid-byte
|
|
_outputBuffer[2] = _spi->transfer(0); // LSB
|
|
|
|
_outputValue = ((long)_outputBuffer[0]<<16) | ((long)_outputBuffer[1]<<8) | (_outputBuffer[2]);
|
|
_outputValue = convertSigned24BitToLong(_outputValue);
|
|
|
|
_cycle++;
|
|
if(_cycle == 4)
|
|
{
|
|
_cycle = 0;
|
|
//After the 4th cycle, we reset to zero so the next iteration reads the 1st MUX again
|
|
}
|
|
}
|
|
|
|
return _outputValue;
|
|
}
|
|
|
|
void ADS1256::updateConversionParameter()
|
|
{
|
|
conversionParameter = ((2.0 * _VREF) / 8388608.0) / (pow(2, _PGA)); //Calculate the "bit to Volts" multiplier
|
|
//8388608 = 2^{23} - 1, REF: p23, Table 16.
|
|
}
|
|
|
|
void ADS1256::updateMUX(uint8_t muxValue)
|
|
{
|
|
_spi->transfer(0x50 | MUX_REG); //Write to the MUX register (0x50 is the WREG command)
|
|
_spi->transfer(0x00);
|
|
_spi->transfer(muxValue); //Write the new MUX value
|
|
}
|
|
|
|
inline void ADS1256::CS_LOW()
|
|
{
|
|
if (_CS_pin != PIN_UNUSED) //Sets CS LOW if it is not an unused pin
|
|
{
|
|
digitalWrite(_CS_pin, LOW);
|
|
}
|
|
}
|
|
|
|
inline void ADS1256::CS_HIGH()
|
|
{
|
|
if (_CS_pin != PIN_UNUSED) //Sets CS HIGH if it is not an unused pin
|
|
{
|
|
digitalWrite(_CS_pin, HIGH);
|
|
}
|
|
} |