Re: Melzi connection/freezing help
Have you tried measuring the resistance of your heatbed?
View ArticleRe: MatchboxARM
Thanks guys, interesting perspective on the limitations, but what about benefits? Can ARM bring anything to the table in terms of cheaper/better electronics for RepRap? Or it's just for variety sake?
View ArticleRe: MatchboxARM
Personally I think ARM is all round better, faster and cheaper, but I have been working with ARM chips since 1999 so they are well inside my comfort zone. I think it's amazing how many functions have...
View ArticleRe: Melzi connection/freezing help
just checked there its about 1 ohm as well. I don't understand how it can change though its been working fine for a month or so. Have you tried the higher current power supply yet or what are your plans?
View ArticleRe: Melzi connection/freezing help
I tried powering the 2 Melzi boards off 2 different 20 amp power supplies (I wanted to make sure power was the issue) it power all the heaters and the bed without issue. I had other issues with this...
View ArticleRe: MatchboxARM
Good point, @bobc. Not cheaper, though, since an ATmega isn't exactly expensive either. And ARMs have only 3.3V signals which isn't sufficient to drive commodity MOSFETs or TB6560 or THB7128 stepper...
View ArticleRe: Melzi connection/freezing help
I am only running one hotend and board just now though so it should not be close to its max. I will try a bigger power supply though. Will there be no issues with it drawing too much current?
View ArticleRe: repstrap electronics
I made a custom board based on a 40 pin atmel atmega 1284, it has a total of 6 PWM channels, 2 for the extruders, 2 for the fans, 1 for the bed and one more that I don't use right now (maybe for a...
View ArticleQuestion about a component connected to the step size selection pins on Melzi...
What's the 'component' connecting MS1 and MS2 on the stepper drivers? http://reprap.org/mediawiki/images/7/7d/Melzi-circuit.png Looking at the physical board, it just looks like two copper pads,...
View ArticleRe: MatchboxARM
That's a fair point. It's a difficult to compare costs, since it's a bit apples and pears, but the cheapest easily available ARM is probably the Kinetis KL25, 128Kb Flash for £2.00. ATMEGA128 is £5.00...
View ArticleRe: Melzi connection/freezing help
If your only running 1 hotend and the heat bed the current should be around 13.5 to 14.5a at 12volts. I like the efuel PSU as you can monitor current flow and adjust the voltage on the fly. I have my...
View ArticleRe: Question about a component connected to the step size selection pins on...
They are pairs of pads shorted by solder blobs. To change the selection you either add the blob or leave it off. The ones I supply have them all shorted for x 16.
View ArticleRe: Question about a component connected to the step size selection pins on...
Ah that makes sense - cheap way to do it I guess!
View ArticleRe: MatchboxARM
@bobc, Having recently gone through microcontroller selection at 1k quantities, I found Atmel was still coming out on top as far as low cost goes. ATSAM, that is. When I added requirements for: USB,...
View ArticleAnyone here using the BeagleBone (Black) to control their 3D printer?
I have a Mendel90 which came in a kit with the Melzi board (Marlin firmware), which works great (in terms of quality of print etc) There's two things that bug me though: 1) The slowness of uploading...
View ArticleRe: Anyone here using the BeagleBone (Black) to control their 3D printer?
The PRU's I think are meant to be flexible communication chips. Instead of installing a chip for every communication protocol, RS232, Ethernet, USB, I2C, CAN, Firewire, etc, etc, etc. They put in...
View ArticleRe: Anyone here using the BeagleBone (Black) to control their 3D printer?
It's most definitely possible to control a stepper driver with the PRUs. Take a look here:...
View ArticleRe: Question about a component connected to the step size selection pins on...
Yes, and there is not really any need to change from x 16 unless you need a step rate faster than the firmware can manage.
View ArticleRe: Anyone here using the BeagleBone (Black) to control their 3D printer?
The BeagleBone looks like a really interesting platform for 3d printing, and the PRUSS are very neat units. Basically like an embedded RISC CPU, and you get two. Possibly a better way to do it than...
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