CNC Controller Board v2

As I said previously, I have been slowly developing my second CNC Machine, TheMaker2. To control the new CNC machine I developed a new board based on a PIC16LF877A since the L297's that I used on the first CNC controller board that I designed can be quite expensive here in Portugal and I had some PIC16LF877A samples lying around that with a few programming lines could do the same or even more than three L297 stepper motor controllers.

(Click the photo for better resolution in Picasa Photostream)

Once again, the board design can be split in three parts:

1. Isolation - it has Vishay's CNY17-2 optocouplers to isolate the parallel port from the rest of the circuit;
2. Driver - a Microchips' PIC16LF877A drives three stepper motors in unipolar mode (if you prefer bipolar you can change the schematics and boards at your will);
3. Power Interface - a bunch of Vishay's SUP85N03 N channel FETs working as switches controlled by the PIC16LF877A.

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Homemade CNC: TheMaker2

Hi! As I previously said in my first post about my first Homemade CNC: TheMaker1, I was slowly developing a bigger, faster (didn't accomplish this part yet) and more robust CNC. Well, the development phase has finally come to an end and it is finally ready! :D In order to build a more rigid structure I decided not to build it with a moving gantry, but with a moving table on x axis and a fixed structure for y axis, which holds z axis. The build is based on this one.

(Click the photo for better resolution in Picasa Photostream)

One of the main objectives was to make it low cost and believe it or not, with some scavenging involved I managed to build the whole structure with only 84.4€! :D Oh, and this cost still includes some spare materials! :P

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The BiT Bang Theory Blog is 1 Year old

Hi everyone! It has been a long time since I last posted something and some of you probably thought that this blog had been forgotten but it didn't :) I have been working on moving the blog from wordpress to blogspot since it gives me more freedom to make this blog unique. Also, since I was moving the blog I kept some stuff to publish in the new version :) But more on that later. First I'm going to make a balance on this first year of tech/hack blogging :) .

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Adding an external power supply to a cheap USB hub

Hi again! In this post I'm going to show you how to add an external power supply to a cheap USB hub. :)

(Click the photo for better resolution in Picasa Photostream)

I've been running some experiments with two Logitech Quickcam for Notebooks Pro and the Raspberry Pi and unfortunately I haven't been getting any good results. I can't get many fps and some of the captured frames contain corrupted data but I think I may have found out the reason for that. After some reading I verified that the USB ports of the Raspberry Pi can only source 100mA to a device and maybe the cameras are consuming more than that. To bypass that problem I went out to buy a USB hub with external power supply.

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How to locate files in linux

Hi! Have you ever needed to find some files in linux? Here's a quick and easy "How To" on it. To locate files you can use the command "locate" (yes, to locate, use "locate", pretty obvious, huh? :P). If you know the name of the file just launch a terminal and write:

locate "filename" 

(Click the photo for better resolution in Picasa Photostream)

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