Solving the USB Latency Dogma for HMI/MPG: Technical Feedback Request

Well aware of how Italians dramatic and exaggerated in their statements, all you have to do is listen to Rossi et al and his comments regarding Marc.

The 7i73 will allow a reasonable HMI with just one cable as well. A 7i90 with SmartSerial firmware works in the same way.

unknown wrote:

The 7i73 will allow a reasonable HMI with just one cable as well. A 7i90 with SmartSerial firmware works in the same way.
 

+1
I have used 7i73 and it was really good. I will use 7i73 again whenever a project calls for it. Still, I celebrate everytime additional hardware support shows up for linuxcnc.

As I said, I had thought of doing this myself, but the fact is, I will never find the time to do everything I think of doing. I am really pleased bobwolf is doing this.

Quick update: I’ve just finished the 'io_decoder _eval' firmware for Arduino Uno.
I'm currently drafting a quick-start guide and a wiring diagram to make the testing process as smooth as possible for everyone.
I expect to release the package (firmware + documentation) this weekend.

Stay tuned!

Hi everyone,

As promised in my last update, I’ve just released the v1.0-eval package, including the driver, the Arduino firmware, and full documentation.

I’ve set up a dedicated project page to host the quick-start guide and the wiring diagrams to make the setup as easy as possible.

What’s included in this release:

HAL Driver: The core engine to interface your USB panel with LinuxCNC.

Evaluation Firmware: Ready to be flashed on your Arduino Uno.

Technical Docs: Wiring schemes and HAL configuration examples.

You can find everything here: Project Home & Documentation: bobwolfrst.github.io/io_decoder-linuxCNC/demo_mode.en

Quick Links:

Direct Download (.zip):
github.com/bobwolfrst/io_decoder-linuxCN..._decoder_eval-v1.zip

Technical Demo: Evaluation Mode & HAL Test Video (showing the real-time response of the physical buttons and MPG in HAL).

I’ve also recorded a short technical demo showing the driver in action: you can see the real-time response of the physical buttons and MPG selector mirrored instantly in the HAL pins.


I’m really interested in your feedback regarding the setup process and the latency you experience on your machines. Let’s break the "USB dogma" together!

ciao
Roberto

I'm interested in trying this out. Where can I get the Arduino source code?

I'm a little unconvinced how changing to USB would have an affect on the "wiring nightmare or EMI issues".

On my machine, I have a 30ft active USB cable going from the control box to the spindle mount (it's for a camera, but I have other wires up there for other things and the cable chain is getting full).  I could see a use for another going to the tool rack (it's on the far side of the machine wrt the control box) for monitoring the pockets etc .  It's no different than running 24V and RS422 between Mesa cards, or ethernet/ethercat, but with hubs and latency
As for noise, I imagine cases where replacing "home runs" to sensors with a single USB cable with CRCs would prevent some EMI spikes from triggering faults.
As always, we each have different needs and having a wide range of options available is good