Raspberry Pi 4

New to the pi game. Just got it installed yesterday. Had a runaway today testing different isolcpus. It was on the default 3 from the 2.8.1 /iso installer file and when I went to jog Z, it kept going until I killed everything. I get constant runaways with my touch screen as well - planar pct2235. Screen works a treat on my 12 year old pc running my router (deb10, 2.8.1, g540). I should mention that the runaway I'm most concerned about was jogging with the keyboard.

With the touchscreen, I'm sure it's a pi driver issue as nothing works reliably (other apps like onboard or just general navigating) but it works great hooked to my other computer. This machine is an emco pc turn 55 with 7i76ed and pi4b.

Also pretty interested in if there are benefits to the 7c80 vs 7i76e/ed with pi?

Main benefits are that you retain your Ethernet port
and the 1 KHZ servo threads are possible

PCW wrote: Main benefits are that you retain your Ethernet port
and the 1 KHZ servo threads are possible

What does the pi/7i76 combo servo thread cap out at? Kinda wish i knew about the 7c81 before ordering those 7i76ed cards, but the pi was an afterthought. I originally wanted to run from a micro pc (u700) but that failed hard (400k latency) :lol:

The Feral Engineer wrote: New to the pi game. Just got it installed yesterday. Had a runaway today testing different isolcpus. It was on the default 3 from the 2.8.1 /iso installer file and when I went to jog Z, it kept going until I killed everything

How were you jogging? MPG? HAL pins? Keyboard? Joypad?

andypugh wrote:

The Feral Engineer wrote: New to the pi game. Just got it installed yesterday. Had a runaway today testing different isolcpus. It was on the default 3 from the 2.8.1 /iso installer file and when I went to jog Z, it kept going until I killed everything

How were you jogging? MPG? HAL pins? Keyboard? Joypad?

I'm getting runaways with the touch screen and the one that scared me most was the keyboard. I'll try and replicate it tomorrow

That sounds like the system isn't receiving keyup events, for some reason.

Keyboard jogging should only go as far as the axis limits, but that is not much of a safety net if you are jogging Z down.

FWIW I don't trust USB / GUI for jogging any of my machines. It's much more dependable to jog via HAL pins, for example with an MPG.
I have never seen the problems you have, but I am aware of the possibility.