How to enable EMERGENCY_PARSER in Marlin firmware?

  • In the documentation of some commands of the Marlin firmware (like M112 - Emergency Stop), it says that the EMERGENCY_PARSER should be enabled to execute them instantaneously.

    The thing is, I didn't find any information there of how to enable that EMERGENCY_PARSER or how it works.

    Any help will be appreciated.

  • 0scar

    0scar Correct answer

    4 years ago

    The constant EMERGENCY_PARSER is located in the advanced printer configuration file Marlin/Configuration_adv.h:

    // Enable an emergency-command parser to intercept certain commands as they
    // enter the serial receive buffer, so they cannot be blocked.
    // Currently handles M108, M112, M410
    // Does not work on boards using AT90USB (USBCON) processors!
    //#define EMERGENCY_PARSER

    To enable the EMERGENCY_PARSER, you need to remove the // before #define EMERGENCY_PARSER and recompile the sources.

    Normally your printer will execute a command until it is ready to accept a next instruction. Without the EMERGENCY_PARSER set, the printer finishes the instruction that it is executing at the moment, if set, the execution is interrupted and immediately sent and thus not waiting for a clear space in the buffer.

    Is there a way to know if `EMERGENCY_PARSER` is set without looking at the printer configuration file (for example, sending a command or checking the first responses when you connect via serial port)? Was this feature added on Marlin 1.1.0?

    @fsinisi90 I don't know if you could try that out. You do need to somehow inject the `M112` in the midst of operation, usually that is done by the code as an emergency response on certain limit checks, I do not know how to insert that manually from outside.

    Well, I've already tried with `M190` (wait for bed temperature) and then `M108` and it's not working, but my firmware is Marlin 1.0.3 and I guess the `EMERGENCY_PARSER` was added on 1.1.0, so I don't even have the possibility to enable it. Anyway, I was looking for a way to check it on any printer from my source code (I'm connecting through pyserial), without human intervention.

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Content dated before 7/24/2021 11:53 AM

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