---
name: "halmeter"
section: "1"
platform: "linux"
package: "linuxcnc-uspace"
version: "1:2.9.4-2+deb13u1"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/halmeter"
---

# halmeter(1)

observe HAL pins, signals, and parameters

## NAME

halmeter - observe HAL pins, signals, and parameters

## SYNOPSIS

**halmeter** \[**-s**\] \[**pin**\|**sig**\|**param** *name*\] \[**-g** *X-position Y-position \[Width\]*\]

## DESCRIPTION

**halmeter** is used to observe HAL (Hardware Abstraction Layer) pins, signals, or parameters.  It serves the same purpose as a multimeter does when working on physical systems.

## OPTIONS

- **pin** *name*

  Display the HAL pin *name*.

- **sig** *name*

  Display the HAL signal *name*.

- **param** *name*

  Display the HAL parameter *name*.

- If neither **pin**, **sig**, or **param** are specified, the window starts out blank and the user must select an item to observe.

  - **-s**

  Small window.  Non-interactive, must be used with **pin**, **sig**, or **param** to select the item to display.  The item name is displayed in the title bar instead of the window, and there are no "Select" or "Exit" buttons.  Handy when you want a lot of meters in a small space.

- **-g**

  Geometry position.  Allows one to specify the initial starting position and optionally the width of the meter. Referenced from top left of screen in pixel units. Handy when you want to load a lot of meters in a script with out them displaying on top of each other.

## USAGE

Unless **\\-s** is specified, there are two buttons, "Select" and "Exit". "Select" opens a dialog box to select the item (pin, signal, or parameter) to be observed.  "Exit" does what you expect.

The selection dialog has "OK", "Apply", and "Cancel" buttons.  OK displays the selected item and closes the dialog.  "Apply" displays the selected item but keeps the selection dialog open.  "Cancel" closes the dialog without changing the displayed item.

## EXAMPLES

- **halmeter**

  Opens a meter window, with nothing initially displayed.  Use the "Select" button to choose an item to observe.  Does not return until the window is closed.

- **halmeter &**

  Open a meter window, with nothing initially displayed.  Use the "Select" button to choose an item.  Runs in the background leaving the shell free for other commands.

- **halmeter pin** *parport.0.pin-03-out* **&**

  Open a meter window, initially displaying HAL pin *parport.0.pin-03-out*. The "Select" button can be used to display other items.  Runs in background.

- **halmeter -s pin** *parport.0.pin-03-out* **&**

  Open a small meter window, displaying HAL pin *parport.0.pin-03-out*. The displayed item cannot be changed.  Runs in background.

- **halmeter -s pin** *parport.0.pin-03-out* **-g** *100 500* **&**

  Open a small meter window, displaying HAL pin *parport.0.pin-03-out*. places it 100 pixels to the left and 500 pixels down from top of screen. The displayed item cannot be changed.  Runs in background.

- **halmeter -s pin** *parport.0.pin-03-out* **-g** *100 500 400* **&**

  Open a small meter window, displaying HAL pin *parport.0.pin-03-out*. places it 100 pixels to the left and 500 pixels down from top of screen. The width will be 400 pixels (270 is default) The displayed item cannot be changed.  Runs in background.

## AUTHOR

Original version by John Kasunich, as part of the LinuxCNC project.  Improvements by several other members of the LinuxCNC development team.

## REPORTING BUGS

Report bugs at https://github.com/LinuxCNC/linuxcnc/issues

## COPYRIGHT

Copyright © 2003 John Kasunich.\
 This is free software; see the source for copying conditions.  There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.