Hamilton STAR firmware error: C0DI / C0AS “Unknown parameter” with older firmware

[Moson2307]

Problem

I am trying to use PyLabRobot with a Hamilton Microlab STAR, but encounter firmware errors during setup and when executing liquid handling commands.

The first issue occurs during lh.setup(), where initialization fails with:

Pylabrobot.liquid_handling.backends.hamilton.STAR_backend.STARFirmwareError: {‘Master’ :CommandSyntaxError(‘Unknown parameter’)}. C0DIid0006er01/31

This suggests to me that the initialization command sent by the backend is not supported by my firmware.

To investigate, I initialized the robot using Hamilton VENUS and then reconnected using PyLabRobot without running lh.setup().

In this state:

• iSWAP commands work
• Tip pickup works only after skipping parts of the backend initialization
• Aspirate fails with:
  Pylabrobot.liquid_handling.backends.hamilton.STAR_backend.STARFirmwareError: {‘Master’ :CommandSyntaxError(‘Unknown parameter’)}. C0Asid0023er01/31

This suggests that even after bypassing initialization, liquid handling commands generated by the backend are incompatible with the firmware.

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Summary:

• Setup fails due to unsupported initialization command (C0DI)
• Aspirate fails due to unsupported command (C0AS)
• ISWAP Movement commands work; tip pickup works with a workaround

The same workflow executes successfully in VENUS using the same hardware.

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Environment

• Python: 3.10.11
• PyLabRobot: 0.2.1
• OS: Windows 11
• Robot: Hamilton Microlab STAR

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Firmware (from VENUS trace file)

• Main module: 8.0S (2011-03-02)
• 1000 µL channels: 3.8S (2013-08-27)
• iSWAP: 4.0S (2007-01-17)

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A snippet of the code used is attached.

[har1eyk]

Thank you for submitting this issue, @Moson2307 .

Will you see if pull request #1002 fixes your error?

[Moson2307]

This worked for me after forcing:

def _pip_has_old_firmware(self) -> bool:
return True

Thanks alot for the quick assistance.