Raspberry Pi weekend project

[Ment11]

I finally received my Raspberry Pi last Friday, and decided to build a computer out of some spare parts I had laying around. I used a CRT viewfinder from an old Sony camera as a monitor, and powered the whole thing from two 11.1V Li-Po's running in parallel. For the Raspberry Pi power supply I just used a simple LM7805 regulator.

I wired up a character LCD to the Raspberry Pi GPIO as well, but unfortunately could not get it working yet. (if anyone knows how to properly interface it please let me know) I still want to wire up a USB hub to it so I can run a wireless card, and build a proper power supply with charging capabilities on board.

If anyone is interested I have more pics, and a more detailed write up on my web site - http://overclocked.tv/diy-projects/pifinder-raspberry-pi-portable-pc-project

[ivan747]

That's quite an odd monitor! Did you use composite video to interface it?

[Ment11]

That's quite an odd monitor! Did you use composite video to interface it?

Yes, I just wired an RCA jack into the original Viewfinder connector, and connected that to the Raspberry Pi analog video out. For power I just wired the viewfinder straight to the batteries (it runs from about 10v to 13v).

[psycho0815]

How exactly did you connect your lcd, i can't make that out in the picture?
The Pi's GPIO-Pins work with 3.3V-logic. Most LCDs need 5, so you need some sort of Levelshifting. Since it's only unidirectioal you can use simple transistors or a darlington array depending on what you have lying around. As for the software, there's plenty of information on accessing those LCDs. Not sure if anyone has already written a library for the Pi.

[Ment11]

How exactly did you connect your lcd, i can't make that out in the picture?
The Pi's GPIO-Pins work with 3.3V-logic. Most LCDs need 5, so you need some sort of Levelshifting. Since it's only unidirectioal you can use simple transistors or a darlington array depending on what you have lying around. As for the software, there's plenty of information on accessing those LCDs. Not sure if anyone has already written a library for the Pi.

The lcd is connected to the Pi straight through, but in read only mode.(R/W pin grounded) The power comes from the 5V regulator. There is a library already written, http://learn.adafruit.com/drive-a-16x2-lcd-directly-with-a-raspberry-pi/overview so all the hard work was already done. So far from what I checked out it's either a python script not running properly, or the LCD is not wired properly. I have a scope with a logic analyzer at work, so I am probably going to check it out when I get some time.