Show Posts
1
SmartBOB controllers and dedicated accessories / PMDX-424 and constant Motion Underrun Error
« on: July 04, 2019, 12:06:26 PM »
I've recently upgraded my home made CNC to the PMDX-424, Mach4, and new drivers and power supply, so essentially a full electronics rebuild. I've been slowly working through constant issues with the upgrade, and got the machine functional, but now I'm running into an extremely persistent 'DEVICE ERROR 'SYSTEM ERROR(7): Motion Underrun'.
I've already attempted to increase my buffer from the 150 default to 450, resulting in no change in the error frequency. And the error certainly is frequent, there are times when it will pop up every tenth of a second, and I just hit enable, cycle start again, the machine will twitch to the next line of code, then the error will pop up again. However, there are times when it will run perfectly fine for hours. For instance, I ran this two hour job last night, and had the error maybe 5 times. I'm halfway through the exact same job this morning and I've probably had it 200 times, and now I'm at the point where I won't even be able to finish it because it is so constant. The error doesn't typically happen when jogging, though it has occurred before.
My initial thought was the PC I'm using to run my whole CNC is just too slow and underpowered, although it worked great for months before upgrading to the PMDX-424 and Mach4. (https://smile.amazon.com/gp/product/B07CJFZ1NL/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) It is a small fanless PC I thought would be good for a dusty environment, but with only 1.92 GHz and 4gb of RAM. I thought adjusting for the buffer would help with this, but it doesn't have seemed too. I'll upgrade if I need to, but I want to make sure this isn't something I could adjust in the settings or script or whatnot.
I understand typically this could occur when there are many small rapid movements, but I'm seeing it when it is cutting a straight path along one axis only as well.
I'm at a loss as to what could be causing this inconsistent, but crippling, error. I've seen postings about maybe optimizing my Mach4 for my particular lead screws and/or steppers, but I'd like to get at least some sort of direction from someone better informed than I before I leap down yet another rabbit hole to get my rig running like I hoped it would after spending $400 on the PMDX/Mach4 upgrade.
I'm running Mach4 Hobby, version 4.2.0.3804, build 3804, screen set wx4.set.
PMDX Plug In Version 0.53.263
PMDX Bootloader Version 1.13.73
PMDX Firmware Version 0.60.208
Thanks,
Kyle
I've already attempted to increase my buffer from the 150 default to 450, resulting in no change in the error frequency. And the error certainly is frequent, there are times when it will pop up every tenth of a second, and I just hit enable, cycle start again, the machine will twitch to the next line of code, then the error will pop up again. However, there are times when it will run perfectly fine for hours. For instance, I ran this two hour job last night, and had the error maybe 5 times. I'm halfway through the exact same job this morning and I've probably had it 200 times, and now I'm at the point where I won't even be able to finish it because it is so constant. The error doesn't typically happen when jogging, though it has occurred before.
My initial thought was the PC I'm using to run my whole CNC is just too slow and underpowered, although it worked great for months before upgrading to the PMDX-424 and Mach4. (https://smile.amazon.com/gp/product/B07CJFZ1NL/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1) It is a small fanless PC I thought would be good for a dusty environment, but with only 1.92 GHz and 4gb of RAM. I thought adjusting for the buffer would help with this, but it doesn't have seemed too. I'll upgrade if I need to, but I want to make sure this isn't something I could adjust in the settings or script or whatnot.
I understand typically this could occur when there are many small rapid movements, but I'm seeing it when it is cutting a straight path along one axis only as well.
I'm at a loss as to what could be causing this inconsistent, but crippling, error. I've seen postings about maybe optimizing my Mach4 for my particular lead screws and/or steppers, but I'd like to get at least some sort of direction from someone better informed than I before I leap down yet another rabbit hole to get my rig running like I hoped it would after spending $400 on the PMDX/Mach4 upgrade.
I'm running Mach4 Hobby, version 4.2.0.3804, build 3804, screen set wx4.set.
PMDX Plug In Version 0.53.263
PMDX Bootloader Version 1.13.73
PMDX Firmware Version 0.60.208
Thanks,
Kyle