Configuring Version 0.99

Alden Hart edited this page Aug 25, 2017 · 22 revisions

The configuration and settings documentation on this page is for firmware version 0.99. FV 0.99 is currently in edge-100 branch undergoing testing. We are pretty comfortable with its functionality and stability, but have a few more functions to install and test before it's promoted to the edge branch. After a soak time in edge it will be promoted to the master branch.

The version number can be found as the fv variable in the startup JSON message, or by typing $fv. Version 0.99 encompasses builds 100.00 and later.

If you have an older firmware version:

Configuration Pages

Conventions Used for Config Documentation

  • Examples show relaxed JSON input. e.g. {fv:n}. Strict JSON is also accepted in all cases, e.g. {"fv":null}
  • Multi-level JSON is shown in its parent/child form, e.g. {x:{vm:...}}. The flat forms are also supported: {xvm:...}
  • CMD means some command - aka the "name" of the name/value pair. CMDs are case insensitive.
  • Underscore "_" means some numeric value
  • "abcd" means some string value
  • Motor examples use Motor 1, but any motor active for your platform is OK
  • Axis examples use X axis, but any axis is OK unless otherwise noted
  • All examples are in millimeter units

A note about units

  • All data entry and display occurs in the prevailing units set in the Gcode mode. Set G20 for inches, G21 for mm. Query {unit:n} or $unit to find out where you are (G20=0, G21=1)
  • Units entered in one system are correctly preserved and do not need to be re-entered or adjusted if the Gcode units mode changes.
  • The Gcode default units setting {gun:_} sets the units the system "comes up in" during power-on or reset. So changing GUN will not change your units until you reset. Note: PROGRAM END (M2, M30) does not change the units.

JSON Cheat Sheet

All configuration commands are available using JSON mode, which is the preferred access method if you are writing a UI or controller. Most commands are also available in Text Mode. The few commands that are available from only one or the other are noted, as are any commands the behave differently depending on the mode. The rough equivalence is:

JSON Text Description
{"cmd":null} $cmd Read value for command "CMD" in strict JSON mode
{cmd:n} $cmd Read value in relaxed JSON mode
{"cmd":123.4} $cmd=123.4 Set value to 123.4 in strict JSON mode
{cmd:123.4} $cmd=123.4 Set value in relaxed JSON mode
{xvm:50000} $xvm=50000 Set X max velocity to 50000 as an example

You can also use JSON to read an entire object - examples for motor and axis:



A command in JSON mode returns a response like the one below. The {} object contains the result, which in this case is a blank JSON object because we sent a Gcode command G0 X10 and have set JSON verbosity to not report back in this case ({jv:3}, for example):


The footer is an array of 3 elements:

  • (1) Footer revision
  • (2) Status code - Short version: status=0 is OK, everything else is an exception.
  • (3) RX buffer info (explained later)
  • Note: The checksum that used to be in the footer has been removed as no-one was using it.
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