Remora - ethernet NVEM / EC300 / EC500 cnc board

Hi Tommylight, I appreciate your comment and I did connect encoders this way you mention in the past and some worked and some didn't, at least not without minor modifications lol. Maybe I didn't explain myself well before, the simplest thing would be an npn-output single-ended open-collector pin-to-pin encoder without confusion, but the first thing I think about when I work with encoders is the noise in the signals because the high switching frequency applied to the stepper coils, it is incorporated into the counting signals, which is why I find it very interesting to maintain the differential channels at least as far as inside the electrical panel. The other thing that I thought about but did not explain clearly in my previous comment is that in closed motors loop that I looked at on ebay and aliexpress doesn't say if the encoder outputs are open collector or not (since the pullup and puldown resistors are added in series to the optocoupler photodiode and can cause unwanted counting pulses), if they are NPN or PNP outputs, or if they are Push-Pull type outputs, and the million dollar question would be if anyone knows of closed loop motors with these characteristics that they can share that would be great hehehe, greetings to all.

chrstrvs wrote:

I noticed that there are two different firmwares in two different locations on GitHub for the NVEM, one in Remora-NVEM/Firmware and the other one in Remora-NVEM/Remora-NVEM-STM32/Firmware.
Which one is the correct one to use for NVEM with STM32F207?

Edit: While browsing around Scott's GitHub I also noticed a repository called Remora-RT1052-cpp. Is this what I should use? If so, from where should I download the remora-nv component? I cant find it in that repo.

Edit 2: Never mind, I saw that the Remora-RT1052-cpp is for boards with RT1052 micro controllers. My initial question is still valid though

this is the firmware you need  github.com/scottalford75/Remora-NVEM/blo...NVEM-STM32-1.0.0.bin
None of the config.txt I provided for the board will work, because you have a NVEM-STM32 those require different board configs. if you check this repository there should be example configs that work.

cakeslob wrote:

Frame size you might have some searching to do, they have 60mm frame size but Im not sure the nema equivalent.
Im fairly sure AC servos will be better, as the motors will probably be 200v. I dont remember if the ac servos get converted back to DC anyway.

When it came to sourcing the motors between AC and DC, my main deciding factor became supply voltage. I found it hard to source the servo drive with my voltage requirements for AC servos, as most I came across were 220v, where DC servo drives I could use 48v DC. My machine is a 110v machine, so it was the deciding factor. If you do not have these limitations, probably go with AC

Yeah my spindle is 220v, so I would rather use AC servos, I seen some on omc-stepperonline but their kind of expensive for the Nm output they have. Also for some reason they seem to be pretty low or out of stock.

If voltage is not an issue, I suggest use AC probably. something like 200W-400W is what your size group will be.

chrstrvs wrote:

Which one is the correct one to use for NVEM with STM32F207?

Yeah good question. Everything is rather confusing at the moment. A newly structured Remora repo is in the works with all firmware, configs and components in one central location, to make everything much easier.

According to the docs , NVEM is the branch you are looking for, as stated before

remora-docs.readthedocs.io/en/latest/har...hernet/ethernet.html

Hi there

To recap, I am trying to setup LinuxCNC with the testing branch of DMA (IE the cpp firmware)

I have formatted a new computer with Debain 12 (Bookworm) as the old computer I was using had had a lot of different softwares during the course of testing various things.

I am running "LINUXCNC - 2.9.0~pre1+git20230208.f1270d6ed7"
And I have put loadrt remora-nv PRU_base_freq=450000 in my HAL file (also changed the remora-nv.c to 500000 )

I have changed the PRU from 80000 to 450000 in stages, but the problem remains.

The problem is this, sometimes when I start LinuxCNC everything runs smoothly & other time when I jog the axis they stutter & stall. I haven't changed anything. When I exit & restart it sometimes fixes itself. There doesn't seem to be any rime or reason.

I know this is all experimental but I thought I'd see if anyone else had come across this.
I have a video of whats happening so see what you think.
Just to repeat the PRU value doesn't change between videos.

youtube.com/shorts/XIrLCH1m3ZI?feature=share

Alex

Perhaps try setting something like this:

"Step Length": 4,
"Step Space": 4,
"Dir Setup": 15

For every joint in the ec500.txt config file that gets loaded on the board via ethernet. Seems like the board is too fast for what your drivers can handle. Just a guess ... Worth triyng

Load it on the board then power cycle it to be on the safe side