Arduino library for TI ADS1258 (24-bit) and ADS1158 (16-bit) SPI ADCs. Provides register-level access plus helpers for common configuration and measurements.

• Supports ADS1258 (24-bit) and ADS1158 (16-bit)
• Read/Write/Update register helpers (read-modify-write)
• Config setters for CONFIG0/CONFIG1 (channel mode, bypass, chop, clock out, status byte, idle mode, delay, bias current, data rate)
• Single read or pulse conversion flows
• Optional status byte handling

#include <ADS1X58.h>

// SPI instance, chip select, vref volts
ADS1X58 adc(&SPI, ADC_TYPE::ADS1258, 10, 2.5f);

void setup() {
	SPI.begin();
	adc.setStatusByte(ADS1X58::STAT_EN); // include status byte in reads
	adc.setChannelMode(ADS1X58::MUXMODE_AUTO_SCAN);
	adc.setDataRate(ADS1X58::DRATE_11); // fastest
}

void loop() {
	float v = adc.readVoltage();
	// use v ...
}

• Auto-Scan Mode: The ADC cycles through a pre-selectable list of channels automatically. Configure using setChannelMode(MUXMODE_AUTO_SCAN), then enable channels via the MUX registers (e.g., write MUXSG0/MUXSG1 for single-ended, or MUXDIF for differential).
• Fixed-Channel Mode: The ADC repeatedly converts a single channel. Configure using setChannelMode(MUXMODE_FIXED_CHANNEL) and select the input in REG_MUXSCH (AINP on bits [7:4], AINN on bits [3:0]).

Example:

adc.setChannelMode(ADS1X58::MUXMODE_AUTO_SCAN);
// Enable AIN0..AIN15 single-ended in auto-scan (helper enables all)
adc.enableSingleEndedInputsOnly();

adc.setChannelMode(ADS1X58::MUXMODE_FIXED_CHANNEL);
// Select AIN0 (P) vs AIN1 (N): write to REG_MUXSCH via updateRegister()
// adc.updateRegister(ADS1X58::REG_MUXSCH, ADS1X58::MASK_MUXSCH_AINP|ADS1X58::MASK_MUXSCH_AINN, (0x0<<4)|0x1);

• Start Pin: Set the Start Pin to HIGH to trigger conversion. Will continuously take new samples if left HIGH. If ADC is in Auto-Scan mode it will automatically index the next channel. Use DRDY and call readChannelDataCommand() or readChannelDataDirect() to fetch the latest result or look at the status byte NEW, see.
• Pulse Conversion (single-shot): Send CMD_PULSE_CONVERT to start a single conversion; library helper: startPulseConversion(). After DRDY, read with one of the read modes.

• Direct Data Read: Wait for DRDY and then use readChannelDataDirect(). No command byte (faster); just hold DIN steady for the first 3 SCLK edges, then clock out data. Risk of corruption if data is not read before the next DRDY.
• Command Data Read: Library uses this in readChannelDataCommand(). Can be read even during DRDY transistion (safer). Sends CMD_DATA_READ_COMMAND (with optional CMD_MUL_EN) and then clocks out data.

• Optional status byte, toggle with setStatusByte(STAT_EN|STAT_DIS):
  • Bit7 NEW new data, Bit6 OFV overvoltage, Bit5 SUPPLY low AVDD warning, Bits[4:0] CHID channel ID
• Data bytes: MSB→LSB
  • ADS1258: 3 data bytes (24-bit two's complement); sign-extend from bit 23
  • ADS1158: 2 data bytes (16-bit two's complement); sign-extend from bit 15
• is handled via ADS1X58_ChanData struct

CONFIG0:

• setInactivityResetTimer(SPIRST_LONG|SPIRST_SHORT)
• setChannelMode(MUXMODE_AUTO_SCAN|MUXMODE_FIXED_CHANNEL)
• setBypassMode(BYPAS_INTERNAL|BYPAS_EXTERNAL)
• setClockOutput(CLKENB_EN|CLKENB_DIS)
• setChopMode(CHOP_EN|CHOP_DIS)
• setStatusByte(STAT_EN|STAT_DIS)

CONFIG1:

• setIdleMode(IDLMOD_SLEEP|IDLMOD_STANDBY)
• setConversionDelay(DLY_0 ... DLY_48)
• setSensorBiasCurrent(SBCS_OFF|SBCS_SMALL|SBCS_LARGE)
• setDataRate(DRATE_00 ... DRATE_11)

Helpers exist to read internal measurements: measVcc(), measGain(), measVref(), measTempC(), measOffset(). These temporarily adjust configuration, perform a pulse conversion, validate CHID, then restore registers.

MIT