---
tag: m0916
title: L6474 Thermal Warning Test
brief: Find L6474 drive level (KVAL_HOLD) threshold
author: shitcreek

requires: MONITOR_L6470_DRIVER_STATUS
group: L6474

codes: [ M916 ]
related: [ M917, M918 ]

notes:
  - Requires `MONITOR_L6470_DRIVER_STATUS`.
  - All tests assume each axis uses matching driver chips.
  - On the L6474 the TVAL is used instead of KVAL.

parameters:
  -
    tag: J
    optional: true
    description: Select which driver(s) to monitor on multi-driver axis
    values:
      -
        tag: 0
        description: (default) Monitor all drivers on the axis
      -
        tag: 1
        description: Monitor only X, Y, Z, E1
      -
        tag: 2
        description: Monitor only X2, Y2, Z2, E2
      -
        tag: 3
        description: Monitor only Z3, E3
      -
        tag: 4
        description: Monitor only Z4, E4
      -
        tag: 5
        description: Monitor only Z5, E5
      -
        tag: 6
        description: Monitor only Z6, E6
      -
        tag: 7
        description: Monitor only Z7, E7
  -
    tag: X
    optional: true
    description: Monitor X with the given displacement (1 - 255mm) on either side of the current position.
    values:
      -
        type: mm
  -
    tag: Y
    optional: true
    description: Monitor Y with the given displacement (1 - 255mm) on either side of the current position.
    values:
      -
        type: mm
  -
    tag: Z
    optional: true
    description: Monitor Z with the given displacement (1 - 255mm) on either side of the current position.
    values:
      -
        type: mm
  -
    tag: E
    optional: true
    description: Monitor E with the given displacement (1 - 255mm) on either side of the current position.
    values:
      -
        type: mm
  -
    tag: F
    optional: true
    description: Feedrate for the moves. (Default max feedrate if unspecified.)
    values:
      -
        tag: feedrate
        type: int
  -
    tag: T
    optional: true
    description: Current (mA) setting for TVAL (0 - 4A in 31.25mA increments, rounds down) - L6474 only. If unspecified, report current value from driver.
    values:
      -
        tag: current
        type: int
  -
    tag: K
    optional: true
    description: Value for KVAL_HOLD (0 - 255) (ignored for L6474). If unspecified, report current value from driver.
    values:
      -
        tag: Kvalue
        type: int
  -
    tag: D
    optional: true
    description: Time (in seconds) to run each setting of KVAL_HOLD/TVAL. (Default zero, to run each setting once.)
    values:
      -
        tag: second
        type: int
---

`M916`: increase KVAL_HOLD until thermal warning.
This routine is also useful for determining the approximate KVAL_HOLD where the stepper stops losing steps. The sound will get noticeably quieter as it stops losing steps.