I’m trying to sort issues I’m having. My first mistake was following an instructional video by ed3d and not realizing the hardware and firmware for my configuration are out of date I suppose.
I downloaded Arduino IDE 2.0.4, the provided ramps 1.4 firmware (every version now), the ug8lib.h library and added the zip to the sketch
After many attempts the farthest I’ve gotten is the marlin load screen with the older versions of firmware. The screen shows XYZ 0 and ?… If I try to move x or y 10mm, x1 and y1 vibrate and then I can’t send the command anymore.
I’m having an error when compiling the newer ramps 1.4 firmware about multiple ug8 libraries which I don’t understand as I only see one added library on line one.
Any help or recommendation is appreciated… I’m open to a new board such as the skr etc. if this could simplify the firmware side of things.
Marlin firmware no longer compiles using the Arduino IDE (under Windows). Ryan has provided instructions for compiling using PlatformIO. If you are building a standard Primo or Lowrider, V1 provides pre-configured versions of Marlin here. In addition, these packages include a pre-compiled hex file, so if you don’t need to make any changes, you can use XLoader to flash your firmware and avoid the compile entirely.
Edit: From a performance standpoint, you will see little difference between the Ramps and the SKR Pro board. If you purchase your SKR Pro from Ryan, it comes pre-flashed with the firmware, but you would still have to flash your board if you purchase the SKR Pro somewhere else. The downside to Ramps boards is they are more fragile. A mistake in wiring will often kill the Mega2560, or burn out a pin. But the upside is that replacing the Mega board is only $20. With that said, there are a lot of MPCNCs using Ramps boards. I have two (non-CNC) projects that use Ramps boards, with zero issues.
I downloaded VScode/platformio last night but had no luck following the steps provided. I opened the ramps folder and then I can’t find the check mark to compile…
I just now followed the link to GitHub to download the Xloader and it must be the wrong Xloader. It only gives device options cc01 or cr03, no Arduino mega.
I’m wondering if something may be wrong with my ramps board. I used Xloader and uploaded the Ramps_2.1.1 hex file, connected the mega to the ramps 1.4 everything seemed to boot up properly but I’m still showing the XYZ 0 and ?. I’ve got jumpers on for 1/32 stepping and I even swapped the drv8825 drivers back to a4988 drivers just to see if they might be the issue and I still have the same problems.
I tried to move any axis I could in increments of 10mm, nothing moved at all except for Y1 just shook a little but did not spin.
I swapped back to the drv8825, I’m not sure on the amp setting as i don’t have a proper multimeter at the moment. I assume even if the current is high or low the steppers should rotate?
I see the v1 screen on boot up and it says 515s.
Also i just have everything in mock up stage to test the electronics.
It will only use 3 drivers unless you use the Dual (MPCNC) or DualLR(Low Rider) version of the firmware. But at least you have flashed it.
The V1CNC_Ramps_Dual is what you want for a MPCNC.
You will need one before you run these for more than a few minutes. The drivers don’t come with the current setting. You can get cheap ones at harbor freight or amazon. They don’t have to be expensive.
I don’t know what setting they are at. They should be ok for this smoke test. But since you are having problems, I am suspicious.
Make sure you have all the jumpers installed under the drivers and the drivers are the right way around.
For XLoader, you want to click on the “Preconfigured Link” for the download. The only difference is the devices.txt file is populated with the info you need in the “Preconfigured” version.
Okay, I believe I have flashed the correct firmware now and thank you for that… I though dual had to do with limit switches.
Also, I just heard that I likely fried my drivers if i hooked up my powered the electronics without the stepper motors plugged in… hopefully I didn’t damage anything else, i ordered new drivers just in case.
Not likely, the drivers all check for open circuit before they do anyrhing, even if you try to move the motor, and they are most definitely OK if you just power on the electronics.
Many 3D printers only use 4 drivers, but the boards have 5 built-in, and the fifth driver doesn’t self-destruct.
What can destroy the drivers is unplugging a motor while the driver is enabled and trying to control the motor, but even that is surviveable by most drivers, it’s just advised against. Motor connectors often have problems with the crimps, causing trouble with the motor disconnecting, and it seldom causes the drivers damage. It does happen, but is less common than the wiring problems are.
Dan is right. This won’t hurt them. The motors have a large inductive load. So you can fry the drivers by yanking the cables when the motors are engaged. But running them without motors is fine.
You need to look at the specs for your steppers to determine the I-max. For most steppers used on MPCNC machines, I-max is around 1.5A, but I’ve seen as high as 2A. Start by setting the current to 80% of that value. So for a 1.5A stepper, 80% would 1.2A. The equation for the DRV8825 stepper driver is:
V-ref = I-max / 2.
The V-ref: 1.2A / 2 = 0.6V. So, you want to rotate your pot on each driver until it reads 0.6V. Your reading of 0.05V is only 0.1A.
Note that the big issue for an MPCNC is the heat of the stepper, not the max allowed current, so be conservative with your V-ref settings to start.
Sure, my drivers are rated for 2 amps and I know they should be at .9 amps. I also made a mistake, my pots are turned all the way COUNTER clockwise, which I believe is at full power and I’m getting the .05 amps reading.
Also turning the pots clockwise even a 1/4 turn gives an amperage reading of 0.
You need to be careful about mixing current and v-ref. V-ref is the read voltage from the stepper driver. For the DRV8825, that is 1/2 of the current output. Your 0.9 does not make sense to me. If 0.9 is the v-ref voltage, that would 1.8A, which is too high for most stepper motors on the MPCNC. If that 0.9 is really the amp rating, that number is too low for most stepper motors that have enough torque for an MPCNC (as spec’ed by Ryan).
You need to start with the maximum amperage for your stepper motor. If the sales page where you purchased the motor did not list it, find the stepper model number and look it up. As I said, most motors with the torque for an MPCNC will have current ratings in the 1.5A to 2.0A range. If you have trouble, post the model number of your stepper motor to this forum, and we can look it up.
As for setting the v-ref, take a look at this picture from the article I referenced above. Notice how he has a clip attached to a screw driver which is turning the potentiometer. Doing it this way allows you to see the v-ref voltage as you very slowly adjust the potentiometer. If the max you can find is really 0.05V, then you may have a bad stepper driver.
Make sure you have your multimeter set for direct current (DC) voltage readings (V).
It may just be the angle of the photos, but first thing I noticed is that the 2 jumper wires are missing from the power input connector. If you do not have both 12 inputs you will not have enough power to run the steppers.
I believe that this is incorrect. The second power input on the RAMPS board is just for the heated bed circuit, and is not used to power the motors at all.
This has to be referenced with the specific drivers. Some drivers are different. This is the case with the DRV8825 drivers that I got, but I have read some have 1:1 relationships of voltage to driver current. I believe that several A4988 drivers are this way. (But not all, like I said, you have to check.)
Regardless, .05V is too low. You should be referencing this from the power supply ground wire.
