How to build ATC Carousel in linuxcnc ?

rogerxue wrote: For example, I see the signal car-enable gets created, but nowhere does it get used,

Where are you looking?

That is linking the signal to the carousel enable, and to a G-code digital output.

my bad, I was looking at a older verison.

So if I decide to use stepgen to drive stepper, then
carousel.N.fwd-dc should be net to stepgen.<chan>.velocity-cmd?

again thanks for the help

rogerxue wrote: my bad, I was looking at a older verison.

Yes, even if you are using LinuxCNC 2.7 you probably want to install the 2.8 version of "carousel".

So if I decide to use stepgen to drive stepper, then
carousel.N.fwd-dc should be net to stepgen.<chan>.velocity-cmd?

Close, except that fwd-dc is an input that tells the component how fast to move in fwd. the actual output to the stepgen is the pin carousel.0.motor-vel

You would need to setp the dc pins to suitable fixed speeds.