Pressbrake CNC Control Setup Questions

I have the homing working on the brake ram, but I end up with negative position readout. It is because I have encoder scale with a negative so that it counts up as it lowers. Should I be reversing the A & B channel wires on the encoder to reverse count direction rather than giving the scale a negative?

Yes, swapping A,B encoder signals will reverse the encoder direction
Beware that this will also change the feedback from negative to positive=runaway
so you need to change the sign of the output scale at the same time

flamecutter wrote: I have the homing working on the brake ram, but I end up with negative position readout. It is because I have encoder scale with a negative so that it counts up as it lowers?

I am working away from home for the next couple of days, but will take a look when I get back. I think down=negative might be baked-in to the code, so let me check.

Is down=positive usual for a press brake?

Yes! I got Axis0 the Brake Ram working!
I kept struggling with the negative position reading, the zero point was below the index. I finally decided it must be applying the home offset wrong. I ventured to change the press component, and subtract the axis_home_offset from the axis_pos_fb_in instead it being added. Line 175 Recompiled it and it worked! Maybe it'll help me develop some troubleshooting skills! Next step is getting the backstop homing worked out.

So, what is the current status?

andypugh wrote: So, what is the current status?

I'm back to working on the backstop homing. No success yet.
I have the brake ram working down=positive with the homing switch at the 0 negative end of travel.
The backstop has its homing switch at the back=positive of the axis travel, opposite direction of the ram.
The backstop has an index pulse approx. every 20mm.
I tried inverting the home switch input, which lets it search in the right direction, but it does not continue long enough to find an index after tripping the home switch.