USING A MPG

The QtDragon interface allows for the use of an external Manual Pulse Generator (MPG) by checking the Enable MPG Jogging checkbox on the SETTINGS page.

A separate HAL file is used to define I/O pins that connect to the MPG and the qtdragon_postgui.hal is used to make the connections to the QtDragon HAL pins.

AXIS SELECT

Four HAL input pins are created to connect the MPG selected axis signals to the Jog joypad highlight segments to indicate which axis is being jogged with the MPG.

SCALE SELECT

A HAL float input pin is created to allow the handler file to display the currently selected jog scale setting of the MPG. Connections from the MPG to a mux4 HAL component are made in a mpg.hal file and the output of the mux4 is connected to QtDragon in order to display the currently selected MPG jog increment. If the MPG is pulse outputs are quadrature encoded, the scale value inputs to the MUX4 component should be the desired step size divided by 4.

MPG DISABLE

A HAL output pin is created to disable the MPG encoder if the Enable MPG Jogging checkbox is unchecked. Note that this does not actually disable the MPG, but is used to disable the encoder on a Mesa ethernet card, if one is used. This will also hide the MPG Scale display from the QtDragon screen.