Hello, perhaps I can get some advice here. I keep thinking this is something simple, but my problem keeps getting worse. I will give the full background in case it is relevant.
I initially built my MPCNC with a cheap ramps board from Amazon running on an old Windows 7 laptop with Repetier host. The setup would sometimes drop communication with the laptop when making heavy cuts. I changed to a longer USB and it got worse. I went back to a 16" USB and rearranged cables and problem went away.
-I switched to a newer laptop running Linux. Once I got the user group thing sorted, it ran great, same as before.
-then I left the machine for 2 weeks, came back and it would not communicate at all. It would connect and then communication timeout on a send code.
-I had planned to upgrade the machine at this time so I ordered a new V1 Rambo 1.4 board with end stops. I got all that installed and began testing with the Windows 7 laptop. And I have been testing soild for a week with no problems dry running many cut programs. Then I started getting some No Start Signal Detected errors. Rebooting the computer seemed to help. Then even after initiating a cut it would drop signal soon after starting, even with router off… Then 2 days ago, it stopped communicating completely. Connects but no start signal.
-My troubleshooting to date has been switching back to the Linux laptop, swapping around 2 known good USB cables, swapping com ports, changing baud rates. I am thinking to try another USB cable?
Check that you have a good ferrite bead on your router. I saw that you said that dry running seemed OK. Did the problems come back after you had the router back on? The interference noise from the router will also be different when under load. A ferrite bead will minimize feedback into the power line
Check filtering on your DC power supply. Not sure what you’re using tgo provid ethe 12V to the RAMPS or the RAMBo. The power supplies that V1 sells are pretty good, but most of the inexpensive ones are pretty weak on regulation and noise filtering. On my first 3D printer, I had to add a couple of big capacitors on the DC output to keep the Mega 2560 happy, and that was at 115200 baud. 250000 baud (V1 default) is even touchier.
If those don’t work, consider a metal enclosure for the RAMPS board. (See Faraday Cage) This will shield the electronics from EM interference which will stabilize the communications.
Last but by no means least, consider using a short-coupled LCD and an SD card to cut off of, or consider cnc.js or Octoprint running on a raspberry Pi with a very short USB cable.
Ok, it makes no difference if router is on or off. It has run fine on Windows 7 for a few months now, but may have run through an update? Seems unlikely. I hooked it up to a big 30 amp power supply and no change. I swapped in the USB from my vinyl cutter, along with the new cable that came with Rambo, and cable that came with my generic board. All known good, no change. “No Start Signal detected”. I have run a lot of stuff in this configuration, now dead. I can’t thing of anything I have changed since lat time it ran well.
I have not gone back again to Linux laptop yet. I am not a Linux guru, so not able to troubleshoot it well
I could try to reload windows driver?
Wow, I just knew it was something stupid but could not find it. I still don’t have a reason why my Linux laptop dropped connection, but I found why the Windows laptop died. The Z-probe and clamp had fallen into a little gap on my table. It must have been touching intermittently and then completed the circuit. Must be a code in the software that does not start if Z is closed. Anyway as soon as I pulled it out, everything ran again.
I don’t want to hear that Jeff. I just set up and started running a critical part. I ran the Z home 5 or 6 times with no problem. I will check the wiring next time I go to my shop and make sure it is plugged into the correct 2 wires in the Z socket of the Rambo board. They are really hard to match up with my crappy eyesight. After that I will try to duplicate the error again just to confirm.
Keep in mind, you are a lot closer to the machine than I am. I am perfectly happy to be wrong. I am not sure how the Z probe could keep it from booting unless it was wired wrong.
I found that my Z probe was plugged into the Z max slot rather than the Z min. So I switched it over after I finished my part. I then proceeded to crash a few times doing dry runs to see of it worked. Seems that you must home X and Y before you home Z or it does some weird things. If I set Z first, then went to X home and it would go through a full X, Y, Z home and drive Z into the base. It did not do that before I swapped. Once I understood this everything seemed OK. I just went to X home, Y home, then set Z home and all seemed ok.