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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Using Piklab with Tiny PIC Bootloader

Following my previous post on How to Setup a PIC Microcontroller Development Environment in Ubuntu 11.10 Oneiric Ocelot With Piklab + SDCC, now I'll show you how to use the Tiny PIC Bootloader with Piklab.

Piklab already has programming interfaces for various programmers, including the Tiny Bootloader. To configure it you must go to "Settings > Configure Programmers... > Tiny Bootloader" and then set your serial port and it's specific settings. In my case, since I use a USB <->Serial TTL Cable (see my previous post on how to make a Low Cost (1,85€) USB to RS232 LVTTL Serial Cable), I configure it with the following data:

• Port Selection: /dev/ttyUSB0
• Specific > Port Speed: 19200
• Specific > Timeout: 300
• Specific > No of Retries: 5

Get the flash player here: http://www.adobe.com/flashplayer

After inserting all the correct configurations for your serial connection, Click "Apply" and you're ready to go. To program you just have to go to "Programmer > Program". Do not forget to click the Reset button of your development board to reset the PIC and initiate bootloader when you want to program it.

Easy, right? Yes, but it doesn't always work. :( I had it working when I used Ubuntu 11.04 Natty Narwhal and some version of Piklab that I can't remember now but since I upgraded to Oneiric Ocelot and a new version of Piklab, the Tiny Bootloader programming interface stopped working. However, there is another easy way to use Tiny Bootloader with Piklab.

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Project Aurora

Hi! Once again some time has passed since my last post. I'd like to post more often but I've been having some busy days. This time I'm writing about a project I developed mostly with my friends and colleagues Gonçalo Pereira and Fábio Martins. The project was slowly developed from December of 2010 to May of 2011 for the event XXVI Semana Académica (26th Academical Week) of the University of the Algarve. The event consists in a full week of partying, with concerts from known portguguese and few international bands. Each course of the university gets a 3x3m tent to sell drinks and raise some money for trips or other purposes. For the Electrical and Electronics Engineering course that we were representing, we decided to make something that had never been done before in that event, something that people are not even used to see in typical bars and discos. Below you can see a video that we made about it, spoken in portuguese but with subtitles in english :).

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How to setup a PIC microcontroller development environment in Ubuntu 11.10 Oneiric Ocelot with piklab + sdcc

Hi! In this blog entry I'll show you how to setup a development environment to develop and compile code for Microchip's PIC microcontrollers. We'll need three main packages:

1. gputils - a collection of tools for the Microchip (TM) PIC microcontrollers. It includes gpasm, gplink and gplib.
2. sdcc - small device C compiler
3. piklab - an integrated development environment (IDE) for applications based on Microchip PIC and dsPIC microcontrollers similar to the MPLAB environment. It integrates with several compiler and assembler toolchains. It supports the most common programmers (serial, parallel, ICD2, Pickit2, Picstart+), the ICD2 debugger, and several bootloaders (Tiny, Pickit2 and Picdem).

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