labjack_u3

EPICS PVAccess server for a LabJack U3 device, implemented with epicsdev.

Main server entry point: labjack_u3/main.py
Phoebus screen generator: screens/generate_screen.py

Features

• U3 initialization and I/O configuration from FIO/EIO strings
• Analog readback:
  • AIN_HV (high-voltage analog inputs)
  • AIN_LV (low-voltage analog inputs)
• Analog outputs:
  • DAC0, DAC1
• Digital I/O read/write (DIO*), based on configured digital channels
• Pulse helpers:
  • Pulse selector
  • PulseFIO*Pars / PulseEIO*Pars
  • pulseTick
• PWM controls:
  • PWM_period, PWM_multiplier, PWM_pulseWidth
• Runtime/status:
  • server, sleep, hardPoll, dateTime, tempU3, rps

Requirements

• Python 3.10+
• epicsdev
• p4p
• LabJackPython (module u3)
• phoebusgen (for screen generation)

Run the server

Typical usage:

• python -m labjack_u3

Useful options:

• -d, --device device prefix base (default: labjacku3_)
• -i, --index device index (default: 0)
• --fio FIO configuration string (default: AAAAaDTC)
• --eio EIO configuration string (default: aaaaDDDD)
• -v increase verbosity

Example:

• python -m labjack_u3 -d labjacku3_ -i 0 --fio AAAAaDTC --eio aaaaDDDD -v

Default PV prefix becomes:

• labjacku3_0:

FIO/EIO configuration

Character codes used in --fio and --eio:

• A = high-voltage analog input
• a = low-voltage analog input
• D = digital I/O
• T = timer
• C = counter

Only channels configured as digital are exposed as DIO* PVs.

Generate a Phoebus screen

Generate .bob file:

• python screens/generate_screen.py

Optional arguments:

• -t, --title screen title
• prefix PV prefix macro/value (default: $(DEV):)

Example:

• python screens/generate_screen.py -t "LabJack U3" "$(DEV):"

Output file:

• screens/labjack_u3.bob

Notes

• If LabJackPython is missing, startup exits with an error.
• The server uses the standard epicsdev control PVs (server, sleep, autosave/recall integration, put logging).