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Re: How to read Hex dump file - 8 years ago

As I said reading back from binary is tough task which is about equivalent to impossible. Which firmware the dump came? Is it Marlin? Marlin is licensed with GPL so there is your right to get the source code. If you bought the printer and you know its firmware and the firmware is licensed as GPL, getting source code is your right. Or has the printer just dropped out of the sky in to your hand

by Vuokko - General

import dxf example? - 8 years ago

I have some DXFs which have bolt holes etc. For this forum I could give example as stepper motor which has four smaller holes in the corners and one bigger in center. So far I have done my .scad files by hand but I'm wondering if I could extrude from dxf drawing the part. And can I just somehow tell openscad to take from layer this and center it and extrude it? The manual is rather brief about i

by Vuokko - OpenSCAD

Re: How to read Hex dump file - 8 years ago

I have found visual diff to be good in such cases. I generate picture of the blob and side by side change the dimensions and then I encode a video. And with the disassembly listing and coordinates I can find a lot of information. I also do much work with IDA and simulators. But that's mainly when finding differences between firmware versions of some devices. Configuring through EEPROM would be

by Vuokko - General

Re: How to read Hex dump file - 8 years ago

You have chosen quite hard task. It is doable, but quite boring, time consuming and results aren't sure. I've don't recommend this way unless you really want learn how computers work. This isn't stuff they teach in universities. This is stuff they write doctoral thesis in reverse engineering. First you need to get AVR-gcc and compile same firmware. Now you have two binaries. Disassemble them. Di

by Vuokko - General

Re: relays for PSU to hotbed and extruder - 8 years ago

If you are using RAMPS and connecting it to heaters and fans connector, I would put some freewheeling diode to protect the transistor. When FET stops conducting, the coil current goes down. Coil in relay is inductor and inductor doesn't want that. It releases its stored energy as higher voltage and might burn your FET. Now putting diode between coil's ends this energy is feed back to coil where i

by Vuokko - Prusa i3 and variants

Re: My Journey to Build a Prusa i3 - 8 years ago

Some (older) PC PSU's need load on 5V too. If I disconnect my Raspberry Pi from 5V line of my bench power supply which is old PC PSU, I get something between 1.5 and 16 volts with awful ripple. But Raspberry loading the 5V line I'm 12.2V with any load. There are some fans running from 5VSB too, but I don't those take much current. Anyway remember load the 5V line so that 12V line doesn't go too

by Vuokko - Reprappers

Re: Which tool to model from photographs - 8 years ago

Like every good photographer, I too put my model through makeup. I gave potato starch coating for it. So it had black and white spots but the resulting point cloud was terribly sparse. That way I have been able to make tight fit cases for wall warts and black shiny batteries. So it has to be the rounding to every direction.

by Vuokko - 3D Design tools

Which tool to model from photographs - 8 years ago

I have plastic piece from Volvo handbrake. I would like to do replacement part with 3D printer. The problem is insane curves of the piece. I've tried couple of times to take photos and feed them to visualSFM and haven't got usable mesh. The cat which wanted to be photographed too made quite nice mesh. As I have some photos, and I can generate them more for my need I'm wondering. Is there any to

by Vuokko - 3D Design tools