Project Scope: A fresh take on an old favorite: take a working NES and add an r-pi to it without destroying the NES in the process
passive USB hub
Short HDMI extension cable (I went with a panel mount option)
Ethernet jack (again I went with a panel mount option)
Playstation 2 to PC adapter
Wireless Playstaion 2 controller
Take a working NES (well, in my case I hope it will be working when I finish
) modify it to hold a raspberry pi inside of it, and use it to stream videos to your TV and play retro gaming systems.
For my setup, I decided that I wanted to use the Playstation 2 wireless controllers, they cost about 15 dollars at gamestop, they have a very good review for working on computers, they're comfortable, and they have the buttons I could want to play all my old school video games... except maybe the sega genesis.
1. Mod the NES
I started first by doing a little house keeping to the NES I disabled the lockout chip and bent the pins on the 72 pin connector upward a little to make a firm contact with the game cartridge (you can read more about this and see other fun mods by going here ).
I'm also planning on swapping out the red led to be blue when the r-pi is on while keeping it red when the nintendo is on. I'm hoping this will result in a purple-ish tint when both are on.
Then came the real modding. There was no spot where the r-pi would actually fit nicely, so I cut out some space on the bottom of the board as shown in this photo (for reference, the power and rest buttons are to the top left of the photo)
I chose this spot for a couple reasons, I didn't have to cut any pylons to get it to fit, and from the outside, you'd never known I had cut it! If you cut any of those other ridges, it makes a big old hole in the bottom of the NES box.
If you remove the expansion box cover on the bottom, you can see the hole from the bottom of the NES
And here it is with the cover back on (what hole?)
Incidentally, I also had to cut the expansion port cover shown here
Here's a picture of the inside with the cover in place. I admit that I didn't make it overly pretty, but this is a part no one sees, so I didn't want to waste a lot of time with it.
Finally, here's a picture of the bottom of the case with a credit card sized object placed in it for reference
Now in hindsight, I made a little snafu. The SD card can't be accessed from outside the case! Oh well, once it's up and running I shouldn't need to swap out the SD card. It's no more an inconvenience than opening up a pc to get the hard drive I suppose.
Step 2 - Powering it
Originally, I was going to power it off a single 9V 3A DC adapter for the Nintendo, I would tap the 9V rail and feed it into a voltage regulator circuit of my design, then after the appropriate voltage regulation, attach it to the two pins in the GPIO strip that have been stolen off the GPIO and attached to the 5V rail instead.
Well to my surprise I find the following little goody in the NES
That's a voltage regulator it accepts a 7-12 V input and outputs 5V DC! Well I'm putting more Amps down it than it can handle so I've decided to swap it out (you can see in the photo above that I've already desoldered it). I'm thinking I want something that will just smooth out the 5V rail and use a 5V PSU rather than a voltage regulator and step it down from a higher voltage. So I'm open to suggestions.
Then all I'd do is jumper what used to be the the input to the output pins of where the voltage regulator used to be and attach my micro usb cable to those + and ground pins at that point. Nintendo gets 5V like it uses and the r-pi get it's 5 volts as well.
Step 3 - More case modding
Once my extension cables get in I'm going to mount the ethernet port and the hdmi port. I'm not worried about anything else on the r-pi since this is just a retro gaming and media center computer.
Step 4 - Front end?
I haven't decided yet, but I think I'd like have the r-pi boot up into a system chooser, it would be a basic menu controlled either by one of the controllers, or by an IR controller (maybe a usb to ir deal, if someone know a more direct way that'd be pretty fun too
) The menu options would either let me choose an emulator to pull up or a media browser. I'm not overly worried about writing a program to choose which program to run, but I'm open to suggestions on the media browser.
I'd prefer something a little cooler than just a file browser that would open a media player. XBMC is a strong contender assuming they port it over of course
but I'm not sure how it would run as an application on the r-pi as opposed to the "OS" so to speak.