herosdevices.hardware.texas_instruments.ads1256

Drivers for the ADS1256 24-Bit, 30kSPS, 8-Channel ADC.

Module Contents

class herosdevices.hardware.texas_instruments.ads1256.ADS1256_CHANNEL

Bases: enum.Enum

Multiplexer channel.

AIN0 = 0

AIN1 = 1

AIN2 = 2

AIN3 = 3

AIN4 = 4

AIN5 = 5

AIN6 = 6

AIN7 = 7

AINCOM = 8

class herosdevices.hardware.texas_instruments.ads1256.ADS1256_GAIN

Bases: enum.Enum

Gain of the programmable gain amplifier.

For voltage ranges for each gain settings refer to ADS1256 datasheet Table 8.

GAIN_1 = 0

GAIN_2 = 1

GAIN_4 = 2

GAIN_8 = 3

GAIN_16 = 4

GAIN_32 = 5

GAIN_64 = 6

class herosdevices.hardware.texas_instruments.ads1256.ADS1256_DRATE

Bases: enum.Enum

Possible A/D Datarates.

Refer to table: DRATE: A/D Data Rate (Address 03h) in the datasheet for more information.

DRATE_30000SPS = 240

DRATE_15000SPS = 224

DRATE_7500SPS = 208

DRATE_3750SPS = 192

DRATE_2000SPS = 176

DRATE_1000SPS = 161

DRATE_500SPS = 146

DRATE_100SPS = 130

DRATE_60SPS = 114

DRATE_50SPS = 99

DRATE_30SPS = 83

DRATE_25SPS = 67

DRATE_15SPS = 51

DRATE_10SPS = 32

DRATE_5SPS = 19

DRATE_2d5SPS = 3

class herosdevices.hardware.texas_instruments.ads1256.ADS1256_REG

Bases: enum.Enum

Registers of the ADS1256.

STATUS = 0

MUX = 1

ADCON = 2

DRATE = 3

IO = 4

OFC0 = 5

OFC1 = 6

OFC2 = 7

FSC0 = 8

FSC1 = 9

FSC2 = 10

class herosdevices.hardware.texas_instruments.ads1256.ADS1256_CMD

Bases: enum.Enum

Command definitions.

Refer to table 24 in the datasheet for details.

WAKEUP = 0

RDATA = 1

RDATAC = 3

SDATAC = 15

RREG = 16

WREG = 80

SELFCAL = 240

SELFOCAL = 241

SELFGCAL = 242

SYSOCAL = 243

SYSGCAL = 244

SYNC = 252

STANDBY = 253

RESET = 254

herosdevices.hardware.texas_instruments.ads1256.delay_us(delay: int) → None

Delay execution by delay microseconds (Uses sleep function).

Parameters:

delay – delay in microseconds.

class herosdevices.hardware.texas_instruments.ads1256.ADS1256(spi_bus: int = 0, spi_device: int = 0, cs_pin: int = 22, rst_pin: int = 18, drdy_pin: int = 17, spi=None, gpio_device: str = '/dev/gpiochip0', default_gain: ADS1256_GAIN = ADS1256_GAIN.GAIN_1, default_drate: ADS1256_DRATE = ADS1256_DRATE.DRATE_30000SPS)

Interfacing the ADS1256 SPI ADC (as e.g. used on the Waveshare high-precision AD-DA board).

reset() → None

Reset the chip by pulsing the reset pin.

config_adc(gain: ADS1256_GAIN, drate: ADS1256_DRATE) → None

Configure the gain and datarate of the ADC.

self_calibration() → None

Run offset and gain self calibration.

set_channel(pos_channel: ADS1256_CHANNEL, neg_channel: ADS1256_CHANNEL = ADS1256_CHANNEL.AINCOM) → None

Set channel of the input multiplexer.

The multiplexer performs a differential measurement between pos_channel and neg_channel. Details can be found in the datasheet under “Input Multiplexer”.

Parameters:

• pos_channel – Positive channel.

• neg_channel – Negative channel. Defaults to AINCOM (non-differential measurement).

set_scan_mode(mode)

read_adc_data() → int

Read ADC value from the currently active channel in bits.

get_channel_value(pos_channel: ADS1256_CHANNEL, neg_channel: ADS1256_CHANNEL = ADS1256_CHANNEL.AINCOM) → int

Read ADC value from the given channel in bits either single-ended or differential.

get_all() → list[int]

Read ADC for all channels subsequently.