Hmm, not sure of the stk500 error, but I can tell you that most linux distributions don't support 250k baud, so stick to 115200. Also, not really familiar with Gentoo, but with Ubuntu and other Debian derivatives, you need to add yourself to a special group to be allowed to make serial connections (the group is "dialout" on Debian types). Finally, you should be able to just plug the board into tby TopherMan - Firmware - mainstream and related support
Oh, just looked up the pins on the Due and the RAMPS layout, and I see what you're saying nophead; it looks like all the VDDs are connected to a 5V pin that's still 5V on the Due. I had assumed they were connected to IOREF.by TopherMan - RAMPS Electronics
I got this from the Pololu website about the A4988: "The driver requires a logic supply voltage (3 – 5.5 V) to be connected across the VDD and GND pins..." Does that mean it will work on a 3.3V system, or does that mean it just needs 3V to run, and still needs the 5V for a signal? Either way, it explicitly says on the DRV8825 page that they work on 3.3V or 5V logic.by TopherMan - RAMPS Electronics
Aah, I didn't make the connection about the /RESET pull-up on the A4988s. RAMPS is built the same way, with /RESET and /SLEEP connected, so when I get one of these I'll be sure to add the resistor. Thanks!by TopherMan - For Sale
Oh, okay. My understanding from the website was that you could just drop it in to slots designed for A4988 and it would work, without any additional modifications.by TopherMan - For Sale
Misan, What's the resistor attached to the FAULT pin for? The website says it was designed so it won't be bothered by a 5V reference signal, and I thought that most of the boards out there just directly attach that pin to the reference pin on the MCU. Did you hack the board so you could read from the pin, or is there some other advantage I'm missing? Thanks, Chris PS. nice heatsink on the oneby TopherMan - For Sale
Okay, I actually get it now. It turns out the Arduino IDE just blindly compiles and uploads any .cpp file in the same folder as the .pde file, so you can just open the basically empty Marlin.pde and upload and it'll work. Seems like one of those "makes it easier for beginners"/"encourages sloppy coding" features. And for the record it works fine on Arduino 1.0 and the beta, 1.5.1. At least, forby TopherMan - Firmware - mainstream and related support
Yeah, I feel a bit dumb; I just figured out that you just compile and upload the Marlin_main.cpp file instead. It worked fine for me in 1.0.2 (and, in fact, also on 1.5.1), so it's all good. I guess I'll suggest a fix for their readme, since it still says to compile and upload Marlin.pde.by TopherMan - Firmware - mainstream and related support
I've been working on updating my copy of Marlin and incorporate some bed probing. However, I switched to a recently-pulled version of Marlin (from the Marlin_v1 branch) and it seems that a recent change cleaned out Marlin.pde. Whenever it was that I originally downloaded Marlin, I could just open it up in the Arduino IDE and hit upload, but now that basically uploads an empty file. I'm not at homby TopherMan - Firmware - mainstream and related support
Excellent, thank you guys. There are so many variants and offshoots of the firmwares that I have trouble finding the exact flavor I need. Hopefully in a few years I will be as good as you two at pretending I know what I'm doing ;-) Now, just a few modifications and I think I can get that to work on my Prusa.by TopherMan - Firmware - mainstream and related support
I was looking through G codes, and I noticed the block G29-G32, the bed probing/leveling commands. I was looking through Marlin and Teacup, and it seems they have not implemented them. Is there any firmware (experimental or not) that has implemented G32 so that it probes the bed and adjusts the print so that it automatically prints onto the almost-level bed? The commercial machine I've used at woby TopherMan - Firmware - mainstream and related support
Testing the voltage on the small tap on the boards I get 0.60 V for the green controllers, and 0.90 V for the black editions. From what I understand from reading the Pololu catalog page about the boards (the section on Current Limiting here), this means the current limit for the motors attached to green controllers is 1.5 A, and for the black 2.25 A. Which, as I was double-checking this, I realizby TopherMan - Stepper Motors, Servo Motors, DC Motors
Also, it's worth noting that the voltages I'm running at are a bit above the rated max voltage for an uncooled chip--I am using the Ultimachine heat sinks and a small fan to cool them.by TopherMan - Stepper Motors, Servo Motors, DC Motors
I think the purple ones with the Texas Instruments chip are not quite drop in replacements, but I seem to recall reading somewhere that the modification to be able to use them is minimal--if I remember to look it up tomorrow I'll post the link here for reference. As far as shipping is concerned, they were wicked fast. Shipped within 24 hours, as promised on their site, and shipped from Nevada. Tby TopherMan - Stepper Motors, Servo Motors, DC Motors
In case anyone is curious, I have been playing with the drivers for the last hour or two, and I've been pleased. As promised, they're drop-in replacements, and can run a bit faster without overheating. I've been able to bump up my z-axis speed from 1.5 mm/s to 2.5 mm/s without having issues with the thermal cutoff from the chip. I've turned up the pot so that the voltage at the tap on the PCB forby TopherMan - Stepper Motors, Servo Motors, DC Motors
Well, since I haven't heard anything, I went ahead and ordered a few. I'll report back for anyone who's interested.by TopherMan - Stepper Motors, Servo Motors, DC Motors
Hey everyone, I just burnt out a stepper on my RAMPS trying to get my z-axis moving. Rookie mistake, but thankfully the drivers are easy to swap out. What I was wondering is if anyone has tried the "Black Edition" of Pololu's A4988 stepper, as described here. They're an extra $4, but it would be nice if they really are noticeably cooler than the standard ones. Thanks a bunch, Chrisby TopherMan - Stepper Motors, Servo Motors, DC Motors
Not sure where you're shipping to, but they are a bit steep, and the shipping to the US at least is a lot. I would recommend Phidgets (phidgets.com), particularly if you're in North America. They have good prices, and their motors are high torque, and they offer 1.8 degree/step and 0.9 degree/step motors.by TopherMan - Reprappers
I am anxiously awaiting the arrival of my 0.9 deg step motors from Phidgets. From the reading I've done, some boards have difficulty keeping up with the calculations if you use a 0.9 deg step motor with 1/16th microstepping, as WildBill mentioned. However, microstepping tends to be slightly less accurate than full steps of comparable size (for example, a full step of a 0.9 deg motor will be moreby TopherMan - Stepper Motors, Servo Motors, DC Motors
Thank you Charlie. Now I think I'm ready to begin assembly!by TopherMan - Reprappers
Okay, cool. One more question; are the bearing-guide parts unnecessary if I use the skate bearings and washers as the assembly instructions recommend? Thanks again, and maybe once I've finished building mine, I'll make some changes to the wiki or the visual instructions to try to bring it up to date. Chrisby TopherMan - Reprappers
Hello everyone, I'm getting started on my first build, and I'm attempting to build the current version of Prusa iter. 2 with lm8uu bearings from github. I've downloaded the .stls and printed them on my work's 3D printer. I'm getting ready to do the actual assembly, and I've read a bunch of the assembly instructions (on the reprap wiki, reprapbook.appspot.com, visual instructions, etc.) and one qby TopherMan - Reprappers