Doing the RepRap #6 — repair, rebuild, rejoice, despair.

In anticipation of fucking shit up I had ordered two ATMegas and having succeeded once it took me one try to get the bootloader to take this time around. The board looked fine, but after a lot of trial and error, error, and error, I resigned to the fact that my Pololus probably were fried and ordered new ones. And that, kids, is how you literally burn 600 SEK by being a lazy bum and not double-checking your solders. Lesson learned and so on.

Having received the new Pololus, and with an extruder underway from the States and the plastic parts coming over from Australia, I only need to get the motors to spin to have a semblance of a printer up and running. I have most metal parts except for some springs and wingnuts, and to celebrate the birthplace of the machine I got some SKF 608 bearings. Oh, and I still need two T5 timing belts.

In the IRC channel I was suggested to use Pronterface.py instead of ReplicatorG as a computer side controller of the board, but after the first few times I couldn’t get the thing to launch and reverted to ReplicatorG. Not that it matters at the moment, because even with the ATMega replaced and properly bootloaded and running Gen7 Teacup, I can’t get any readings or functions out of it. I made a video of my attempts and you can watch it below; it’s dry but you get to watch me prod an inanimate object with clumsy fingers.

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Mom and Tomasz decided to visit now as well. I’ve shown them the archipelago and then my allotment garden and then the KKV workshop and then mom left and now Tomasz is stuck with me while I whine about the RepRap and hush him while recording troubleshooting videos. You can actually hear him in the video above, so it’s well worth watching for that alone! Also, I totally destroyed him at pingpong earlier today, and have video of that as well.

Doing the RepRap #5 — The fun of frying

Good god damn goat balls.

I finally got the bootloader onto the ATMega — thanks to a lot of trial and error and handwringing and help from ethereal beings on the Internets and KKV, and with the motors and Pololus installed I hook the PSU into the board and the LEDs are shining and — wait a minute, isn’t the processor a teensy bit too hot? Oh, let’s touch it — well whaddayaknow, it’s blistering my finger, how peculiar!

As it turns out, I’ve soldered the Molex connector the wrong way around, so am feeding 5V to where I need 12V and vice versa. Which means some components are now fucked, possibly including the ATMega. I guess I ought to be grateful that none of the capacitors blew up in my face, but right now I’m just going to bed.

Below are some helpful links left for future reference

I found a good description for what the bootloading process is about here: http://smileymicros.com/blog/2011/03/04/busy-as-a-beavratmega644-on-a-breadboard/

Resources on what AVR’s are: http://www.evilmadscientist.com/article.php/avrstuff

A tutorial on what AVR programming is about, somewhat technical: http://www.ladyada.net/learn/avr/

Using the AVR ISP MkII as a programmer to bootload ATMegas. Relevant if I get me the programmer, but can give inside into the process: http://www.arduino.cc/playground/Code/OSXISPMKII

Crosspack is a complete AVR developing package, not sure how to implement the homebrewn boards there, but the bootloaders should be more or less generic, right? http://www.obdev.at/products/crosspack/index-de.html

Wormfood has a baud to Mhz calculator here, which I’m sure is good for something down the line: www.wormfood.net

A thread started in 2006 about the process of getting the Arduino to act as an ISP, which I never succeeded in doing: Turn Arduino into an ISP programmer

The schematics for my model of Arduino, the old NG, are here: arduino_NG_schematic.png and there’s a description of most of the parts and ports here: www.arduino.cc

I’m not sure of what this page does but it seems handy: http://www.sengpielaudio.com/calculator-ohm.htm