IO Board

Overview

An IOBoard is a device with one or more analog and/or digital input/output channels. In Blackchirp, an IOBoard takes a single measurement at designated time intervals to monitor analog or digital signals. Analog channels can be read as rolling data for continuous monitoring as well as auxiliary data during a scan. Digital channels are read as auxiliary data during a scan and can be used to automatically abort a scan when a validation condition is violated.

Blackchirp does not drive analog or digital output signals, even on devices that support it.

Settings

The IOBoard reuses many of the same settings as the FTMW Digitizer, and the hardware dialog presents them with inline labels and tooltips. Most digitizer-only settings (maxRecordLength, canBlockAverage, multi-record options, and so on) are ignored because the IO board only reads one sample on demand.

Two settings are worth highlighting:

  • numAnalogChannels selects how many channels are configured as analog inputs on devices where channels can be reassigned (such as the LabJack U3). It is a Required setting and is read-only after profile creation.

  • numDigitalChannels sets the number of digital input/output channels and is similarly read-only after profile creation.

Per-channel role and naming options are exposed in the IO Board configuration page of the hardware dialog.

Drivers

Virtual

A dummy driver that returns a random value for each enabled channel (8 analog channels, 8 digital channels).

LabJack U3

The LabJack U3 is a multichannel, configurable IO board with a variable number of analog/digital channels. The driver defaults to 8 analog inputs (pins 0-7, corresponding to the 4 analog inputs and the first 4 FIO pins) and 8 digital input/outputs corresponding to FIO4-11. Setting numAnalogChannels to 4 frees pins for up to 12 digital channels; values below 4 are not supported and may produce errors at runtime.

The LabJack U3 is supported on Linux, macOS, and Windows. Linux and macOS builds talk to the device through the liblabjackusb Exodriver; Windows builds use the LabJackUD driver instead. Either way, the vendor driver must be installed on the host and discoverable by Blackchirp. See Library Status for the current driver load state and platform-specific installation guidance.