API documentation

opendaq.daq module

Main functions used to communicate with the device. See usage.rst for additional info.

class opendaq.daq.CMD

Bases: enum.IntEnum

AIN = 1

AIN_ALL = 4

AIN_CFG = 2

BURST_CREATE = 21

CAPTURE_INIT = 14

CAPTURE_STOP = 15

CHANNEL_CFG = 22

CHANNEL_DESTROY = 57

CHANNEL_FLUSH = 45

CHANNEL_SETUP = 32

COUNTER_INIT = 41

EEPROM_READ = 31

EEPROM_WRITE = 30

ENABLE_CRC = 55

ENCODER_INIT = 50

ENCODER_STOP = 51

EXTERNAL_CREATE = 20

GET_CALIB = 36

GET_CAPTURE = 16

GET_COUNTER = 42

GET_ENCODER = 52

GET_STATE_CHANNEL = 35

GET_TRIGGER_MODE = 34

ID_CONFIG = 39

LED_W = 18

PIO = 3

PIO_DIR = 5

PORT = 7

PORT_DIR = 9

PWM_DUTY = 12

PWM_INIT = 10

PWM_STOP = 11

RESET = 27

RESET_CALIB = 38

SET_ANALOG = 24

SET_CALIB = 37

SET_DAC = 13

SIGNAL_LOAD = 23

SPISW_CONFIG = 26

SPISW_SETUP = 28

SPISW_TRANSFER = 29

STREAM_CREATE = 19

STREAM_DATA = 25

STREAM_START = 64

STREAM_STOP = 80

TRIGGER_SETUP = 33

WAIT_MS = 17

class opendaq.daq.DAQ(port, debug=False)

Bases: object

This class represents an OpenDAQ device.

clear_experiments()

Delete the whole experiment list.

close()

Close the serial port.

conf_adc(pinput=8, ninput=0, gain=0, nsamples=20)

Configure the analog-to-digital converter.

Get the parameters for configure the analog-to-digital converter.

Parameters:

• pinput – Positive input [1:8].
• ninput – Negative input.
• gain – Analog gain.
• nsamples – Number of samples per data point [0-255).

Raises:

ValueError

create_burst(*args, **kwargs)

Create Burst experiment.

See the DAQBurst class constructor for more info.

create_external(mode, clock_input, *args, **kwargs)

Create External experiment.

See the DAQExternal class constructor for more info.

create_stream(mode, *args, **kwargs)

Create Stream experiment.

See the DAQStream class constructor for more info.

enable_crc(on)

Enable/Disable the cyclic redundancy check.

Parameters:on – Enable/disable CRC checking (bool).

flush()

Flush internal buffers.

flush_channel(number)

Flush the channel.

Parameters:number – Number of DataChannel to flush. Returns:ValueError

get_adc_calib()

Get the ADC calibration.

Returns:List of ADC calibration registers

get_capture(mode)

Get Capture reading for the period length.

Parameters:mode – Period length (0: Low cycle, 1: High cycle, 2: Full period) Returns:

• mode
• period: The period length in microseconds

Raises:ValueError

get_counter(reset)

Get the counter value.

Parameters:reset – reset the counter after perform reading (boolean).

get_dac_calib()

Get the DAC calibration.

Returns:List of DAC calibration registers

get_encoder()

Get current encoder relative position.

Returns:Position: The actual encoder value.

get_info()

Read device information.

Returns:[hardware_version, firmware_version, device_id]

get_state_ch(number)

Get state of the DataChannel.

Parameters:number – Number of the DataChannel. Raises:ValueError

init_capture(period)

Start Capture Mode around a given period.

Parameters:period – Estimated period of the wave (in microseconds). Raises:ValueError

init_counter(edge)

Initialize the edge counter and configure which edge increments the count.

Parameters:edge – high-to-low (False) or low-to-high (True).

init_encoder(resolution)

Start Encoder function.

Parameters:resolution – Maximum number of ticks per round [0:65535]. Raises:ValueError

init_pwm(duty, period)

Start PWM output with a given period and duty cycle.

Parameters:

• duty – High time of the signal [0:1023](0 always low, 1023 always high).
• period – Period of the signal (microseconds) [0:65535].

Raises:

ValueError

is_measuring

True if any experiment is going on.

open()

Open the serial port.

read_adc()

Read data from ADC and return the raw value.

Returns:Raw ADC value.

read_all(nsamples=20, gain=0)

Read data from all analog inputs

Parameters:

• nsamples – Number of samples per data point [0-255] (default=20)
• gain – Analog gain (default=1)

Returns:

Values[0:7]: List of the analog reading on each input

read_analog()

Read data from ADC in volts.

Returns:Voltage value.

read_eeprom(pos)

Read a byte from the EEPROM.

Parameters:

• val – value to write.
• pos – position in memory.

Raises:

ValueError

read_pio(number)

Read PIO input value (0: low, 1: high).

Parameters:number – PIO number. Returns:Read value. Raises:ValueError

read_port()

Read all PIO values.

Returns:Binary value of the port.

remove_experiment(experiment)

Delete a single experiment.

Parameters:experiment – reference of the experiment to remove. Raises:ValueError

send_command(command, ret_fmt=None)

Build a command packet, send it to the openDAQ and process the response.

Parameters:

• command – Command string.
• ret_fmt – Payload format of the response using python ‘struct’ format characters. I ret_fmt is None, no response is expected.

Returns:

Command ID and arguments of the response.

Raises:

LengthError: The legth of the response is not the expected.

serial_str

set_adc_calib(regs)

Set the ADC calibration.

Parameters:regs – A list of CalibReg objects. Raises:ValueError, IndexError

set_analog(volts, number=1)

Set DAC output (volts). Set the output voltage of the DAC.

Parameters:volts – DAC output value in volts. Raises:ValueError

set_dac(raw, number=1)

Set DAC output (raw value). Set the raw value of the DAC.

“param raw: Raw ADC value. :raises: ValueError

set_dac_calib(regs)

Set the DAC calibration.

Parameters:regs – A list of CalibReg objects. Raises:ValueError, IndexError

set_id(id)

Identify openDAQ device.

Parameters:id – id number of the device [000:999] Raises:ValueError

set_led(color, number=1)

Choose LED status. LED switch on (green, red or orange) or switch off.

Parameters:color – LED color (use LedColor). Raises:ValueError

set_pio(number, value)

Write PIO output value. Set the value of the PIO terminal (0: low, 1: high).

Parameters:

• number – PIO number.
• value – digital value (0: low, 1: high)

Raises:

ValueError

set_pio_dir(number, output)

Configure PIO direction. Set the direction of a specific PIO terminal (D1-D6).

Parameters:

• number – PIO number.
• output – PIO direction (0 input, 1 output).

Raises:

ValueError

set_port(value)

Write all PIO values. Set the value of all Dx terminals.

Parameters:value – Port output byte (bits: 0:low, 1:high). Raises:ValueError

set_port_dir(output)

Configure all PIOs directions. Set the direction of all D1-D6 terminals.

Parameters:output – Port directions byte (bits: 0:input, 1:output). Raises:ValueError

spi_config(cpol, cpha)

Bit-Bang SPI configure (clock properties).

Parameters:

• cpol – Clock polarity (clock pin state when inactive).
• cpha – Clock phase (leading 0, or trailing 1 edges read).

Raises:

ValueError

spi_setup(nbytes, sck=1, mosi=2, miso=3)

Bit-Bang SPI setup (PIO numbers to use).

Parameters:

• nbytes – Number of bytes.
• sck – Clock pin.
• mosi – MOSI pin (master out / slave in).
• miso – MISO pin (master in / slave out).

Raises:

ValueError

spi_write(value, word=False)

Bit-bang SPI transfer (send+receive) a byte or a word.

Parameters:

• value – Data to send (byte/word to transmit).
• word – send a 2-byte word, instead of a byte.

Raises:

ValueError

start()

Start all available experiments.

stop(clear=False)

Stop all running experiments and exit threads.

Parameters:clear – If True, the experiment list will be cleared. The

experiments will no longer be available.

stop_capture()

Stop Capture mode.

stop_encoder()

Stop encoder

stop_pwm()

Stop PWM

trigger_mode(number)

Get the trigger mode of the DataChannel.

Parameters:number – Number of the DataChannel. Raises:ValueError

write_eeprom(pos, val)

Write a byte in the EEPROM.

Parameters:id – id number of the device [000:999]. Raises:ValueError

class opendaq.daq.LedColor

Bases: enum.IntEnum

Valid LED colors.

GREEN = 1

OFF = 0

ORANGE = 3

RED = 2

Experiment classes

class opendaq.experiment.DAQBurst(mode, period, npoints=10, continuous=False, buffersize=4000)

Bases: opendaq.experiment.DAQExperiment

Burst experiment.

Parameters:

• mode – Define data source or destination (use ExpMode).
• period – Period of the stream experiment (microseconds) [1:65536]
• npoints – Total number of points for the experiment [0:65536]
• continuous – Indicates if the experiment is continuous (False: run once, True: continuous).
• buffersize – Buffer size

Raises:

LengthError (too many experiments at the same time), ValueError (values out of range)

class opendaq.experiment.DAQExperiment

Bases: object

add_points(points)

Write a single point into the ring buffer.

analog_setup(pinput=1, ninput=0, gain=1, nsamples=20)

Configure a channel for a generic stream experiment.

get_mode()

Return mode.

get_params()

Return gain, pinput and ninput.

get_preload_data()

Return preload_data and preload_offset.

load_signal(data, offset=0)

read()

Return all available points from the ring buffer.

trigger_setup(mode=<Trigger.SW: 0>, value=0)

Channge the trigger mode of datachannel.

Parameters:

• mode – Trigger mode (use Trigger).
• value – Value of the trigger mode.

Raises:

ValueError

class opendaq.experiment.DAQExternal(mode, clock_input, edge=1, npoints=10, continuous=False, buffersize=1000)

Bases: opendaq.experiment.DAQExperiment

External experiment.

Parameters:

• mode – Define data source or destination (use ExpMode).
• clock_input – Digital input used as external clock
• edge – New data on rising (1) or falling (0) edges [0:1]
• npoints – Total number of points for the experiment [0:65536]
• continuous – Indicates if the experiment is continuous (False: run once, True: continuous).
• buffersize – Buffer size

Raises:

LengthError (too many experiments at the same time, ValueError (values out of range)

class opendaq.experiment.DAQStream(mode, number, period, npoints=10, continuous=False, buffersize=1000)

Bases: opendaq.experiment.DAQExperiment

Stream experiment.

Parameters:

• mode – Define data source or destination (use ExpMode).
• period – Period of the stream experiment (milliseconds) [1:65536]
• npoints – Total number of points for the experiment [0:65536] (0 indicates continuous acquisition).
• continuous – Indicates if experiment is continuous (True) or one-shot (False).
• buffersize – Buffer size.

Raises:

LengthError (too many experiments at the same time), ValueError (values out of range)

class opendaq.experiment.ExpMode

Bases: enum.IntEnum

Valid experiment modes.

ANALOG_IN = 0

ANALOG_OUT = 1

CAPTURE_IN = 5

COUNTER_IN = 4

DIGITAL_IN = 2

DIGITAL_OUT = 3

class opendaq.experiment.Trigger

Bases: enum.IntEnum

Valid trigger modes.

ABIG = 10

ASML = 20

DIN1 = 1

DIN2 = 2

DIN3 = 3

DIN4 = 4

DIN5 = 5

DIN6 = 6

SW = 0