Hey guys, I switch to a mega in hopes that it would work better.

Hey guys,

I switch to a mega in hopes that it would work better. using /jpadie, grbl-mega doesnt appear to work. is it supported?


I never managed to get grbl working on the mega. I tried for a couple of days.

The issue seemed to be that there was a race condition on system reset which was being pulsed by cp (or by spjs anyway). I think I got past this by putting a cap across the Vin and reset line to keep it pulled high.

Can someone tell me in layman’s terms what the difference is between SPJS and Universal gcode sender? Are they both servers? And, why is it I need an FTDI chip for most of my controllers, but I either don’t need them for others or they are already installed in the software of others. Just curious.

For all boards that connect to the usb port you need a usb to serial chip. In some cases this will be part of the microprocessor itself. In others it will be an ftdi or ch340g or a dedicated atmel 16u2 or similar chip. And it is also possible that you use an adapter for a direct serial connection. In which case almost certainly the adapter is just a mini board with one of the foregoing in it.

At one level spjs is similar to part of the functionality of ugs. It receives input and pushes it out a port.
However spjs buffers the actual port and then mirrors it as a websocket port. So you can think of it more as a dumbwaiter between the usb interface and the web browser.
Another core difference is that ugs is regarded as “purer” because it does no rewriting of inbound or outbound messages whereas, at least in its grbl buffer, spjs does do so. There are some people that get antsy about this.

Interesting and fascinating. Quite a bit over my head