Reverse Run

Hello,

I'm using LinuxCNC 2.8.1. The release notes of 2.8.0 state that there is a new feature for reverse run:

Reverse-Run: Negative feed-override will now run the G-code path in reverse.

I'm using the following set-up for the feed-override:

However when I now input negative values for halui.feed-override.counts the resulting halui.feed-override.value is just 0 and no reverse movement (see below):

Not sure if I'm missing out here something... Any help appreciated...

Best regards,

Marc

I think that there is an error in the release note. (I will correct it)

It isn't feed-override which enables reverse-run, it is negative adaptive-feed.

You need to set motion.adaptive feed to a negative value. (typically this would be done with some form of sensor, rather than with a jogwheel)

From the motion manpage:

motion.adaptive-feed IN FLOAT
When adaptive feed is enabled with M52 P1, the commanded velocity is multiplied by this value. This effect is multiplicative with the NML-level feed override value and motion.feed-hold. Negative values are valid and will run the G-code path in reverse.

Thanks, works like a charm

PS: ...why this needs to be enabled by M52 P1 and is not active by default? Would not hurt as long as adaptive-feed is not modified....

I think it has a G-code switch because it was originally intended to be driven by a spindle load meter, and you might not want that all the time.