In a pursuit of fabricating pcb’s, I have won. I had designed pcb’s boards using PCB. But when I tried to fabricate the pcb in my home, I used to fail. the problem was with the Acrobat Reader . When I take the print out on the paper for layout transfer to the board, a size change occurs to the layout. This size change make the layout completely useless. Actually it was the wrong option selected in Acrobat Reader that made the size change.Now it is OK.
This is development board designed by me for the ATmega8 microcontroller. It is a miniature ARDUINO. You can burn your bootloader and then use with Arduino IDE or you can simply upload your hex file using DAPA programmer circuit. If anyone needs its schematic file please post an comment or I will soon upload it when I am free.
Anyway this is an open hardware project. I will try to upload the details soon. If you are in a hurry, please comment so that I can upload the details fast.
Here is the PCB layout files http://jeffrey.co.in/files/mini-AVR.pcb
These are the two snap shots of my board
Arduino is one of the coolest board to start learning microcontroller programming. You can get a whole lot of documents from the internet. It’s an Open Hardware project. So that you are free to distribute it, copy it, modify it…. like a free software. Open hardware is a latest trend in the electronics field.
One of the problems of Arduino was that, it’s designs were done using a proprietry software named Eagle. Although free version of eagle is available from the net, it is not a free software. Also the free version of eagle has a limitation that we cannot design large boards.
So I thought of redesigning the Arduino Single-Sided Serial Board (version 3) board using free software gEDA (GNU Electronic Design and Automation) tool. These are the design files of the board.
These files are released under Creative Commons Attribution Share-Alike License 2.5. You can use this file anywhere you want same as like the arduino license. Please give me proper credits while using this file and also give a link back to my page http://jeffrey.co.in/
I have designed this board by tracing the pcb layout of arduino which was designed using eagle. A small tutorial of tracing pcb’s by DJ Delorie is shown here .
Place these two files in a folder. Now in the terminal run the command
pcb –bg-image 125_90.ppm ard.pcb
You can see the pcb tracks over the arduino pcb design which was done using eagle. The pcb tracks were drawn on the component side. While loading the file, PCB will be showing the component side. So you will be seeing the tracks not sitting on the background image. To switch to the solder side press the “TAB” button. Now you will see the track alligned.
Please check the files for any mistakes. If there is any, please comment it.
If you have any comments please do it…
See this page http://web.media.mit.edu/~silver/drawdio/play.htm
I decided to build that pencil. I collected documents from Ladyada’s Drawdio page. The TLC 551 IC was not available in the electronics market in THRISSUR. Actually TLC 551 is a low voltage version of LM 555. So I decided to replace TLC 551 with LM 555.
After building the circuit, I fed it with 5V supply. Since it was LM 555 I fed 5V. If it were TLC 551 we can use a AAA battery to power the circuit.
But the transistor started to heat up. I think that the transistor (amplifier) circuit was designed to be powered from AAA battery. So the 5V might have made it to heat up.
There comes my hack. It’s not actually a hack. I found that we can easily replace the amplifier circuit and the speaker with a buzzer. I have redrawn the circuit with the buzzer. You can download the modified circuit.
This circuit succeeded for a 5V powered LM 555 circuit. But I don’t think it will work if you use a AAA battery to power the circuit and also replacing the LM 555 with TLC 551. If the circuit is powered by a AAA battery, the buzzer wont produce sound that is much audible. so in that case you will have to use the amplifier and the speaker circuit.
These are the two snapshots that has been modified from
Use this snaps together with the circuit diagram to build the DRAWDIO. See these snaps. These are test run done by me on the breadboard.
I had never tought of having an CCD camera in my optical mouse.
But now after reading this site (http://spritesmods.com/) I was suprised.
Actually the optical mouse contains two chips inside: the optical sensor and a chip for the usb/ps2-interfacing. The optical sensor is a tiny 18×18 CCD. Using this sensor we can see small images. The author has written a small app to see the images on the screen through the parallel port.
See this link to find more about this here.
Check his site for more hacks http://spritesmods.com/