switching from parport to mesa 7i96 -- check my assumptions

Thanks for the heads up re: that thread. I'll take a look. And good to know that the RPi5 is so fast. Haven't had a chance to try one yet. Maybe someday. But yes, if my RPi 4 doesn't work out, definitely I'll switch back to a PC. (I don't have high hopes for the RPi.

My current PC still works (in fact, running Wheezy with 2.7.4, from ram off of a thumb drive), but it gives nasty warnings if I try and install something new, and it's old enough that I'd rather replace it on my schedule than wait for it to fail. And with the 7i96, I'll get to clean up some really messy wiring that's waiting to fail, as well. So I'm kind of looking forward to the change.

Just install 2.94 from the downloads page for either the pi or a PC. Just use pnccconf to make a basic config and confirm movement, then cut and paste your current details into it. Take care with that as there are few different things now than 2.7. Mainly the spindle pin is now spindle.0.on

Yes, the docs make it pretty clear I should start with a fresh install.

I'm wondering though: My wheezy-based 2.7.4 system is still running on my old PC. It's been fairly heavily customized, with a custom PYVCP panel addon, a custom POSTGUI_HALFILE to support my gamepad wand, and a custom HALFILE which is used to square up my axes, and which depends on a halcompile'd module (Thanks again for your help, @rodw: forum.linuxcnc.org/10-advanced-configura...rors?start=10#106073)

I'm thinking perhaps I should do a fresh install of 2.9 on the old PC, and get it running all of my customizations on the new release, before moving over to the Rpi+Mesa setup. Just to separate the tasks somewhat. Does that make sense? Or maybe that would just make needless extra work.

Well, that was quick. The customizations are all applied. The update script did a good job, but did miss one thing, in case anyone cares: the main HAL file for my mill led with the following loadrt lines:
I think the final "[TRAJ]AXES" should have been changed to "[KINS]JOINTS", at least if I'm reading the update_ini code correctly. But it was not, leading to "Ini variable '[TRAJ]AXES' not found".  Please correct me if I'm wrong, since I've made the change manually.  (For the record, my config file had no [EMC]VERSION line.)

So now all I need is for USPS to deliver my Mesa card.

Yeah just change it to match the name in the ini file, I think the names are pretty agnostic, think variables or similar in C, with a convention in naming that makes it more readable. As long as the value on the right hand side is correct.
If I'm wrong you have my permission to beat me with a stick.
Cheers
Rob