Bride of Frankenstein, a R-Pi2 in a NES case, the sequel.

[DaOld Man]

Ok, I have another empty NES in the mail, and some parts to go with it.
I dont plan on going into great details on this one, it should be just a repeat of the last one.

Link to the last one:
R-Pi2 NES Frankenstien

But I would like to detail how I mounted the USB ports in the NES controller connectors, how I modified the NES power/reset board to work with the mausberry switch, and to keep a cost of all the parts.
I hope this will help others who decide to do this. And I expect people to greatly improve on my methods.

In the mail or already purchased so far:

NES case $17.00 (Including shipping)

Pi2 $35.00 (MCMelectronics.com)
Power supply $5.39 (Mcmelectronics.com)
2X USB panel mount connector cables $0.93 each (discount code I found on the net applies to these) Total $1.86
1X RJ45 ethernet panel mount connector 11" cable $5.09 (mcmelectronics.com)
Shipping from mcmelectronics.com 7.99

1X panel mount HDMI connector 12" cable. (Ebay $4.49)

Mausberry circuits switch $15.99 (mausberrycircuits.com, including shipping)

PNY 16 GB micro SD card class 10 from Walmart. $9.99

Sub total: $102.80

What I have left over from last project (will tally up cost per item later).
Panel mount AV connector
AV cable
2X panel mount USB connector cables.

Im having a hard time finding the panel mount two prong connector I used for the power entry. May make a run to Goodwill to see if I can find an old cheap stereo with one, or just use the three prong connectors that come on old ATX power supplies. I have a few of those laying around.

[Slippyblade]

I like the two prong power connector, the three prong ones are just so big!

[DaOld Man]

Me too, SlippyBlade, Im still looking for a plug, Goodwill turned up zilch, looks like their electronic stuff is thinning out, hardly nothing at all.

Just a quick update to say i got all my parts in. The friend who sold me the NES case threw in a NES controller, original type. He has another that is on the way.
I decided to use the original plugs and controllers, and tie them into the GPIO on the Pi. (No need to massacre the original plugs on this one.)
I intend to still install USB ports under the cartridge door, like I did on the first one, just so i can use the USB SNES controllers for other emulators.
Hopefully I will get to play around with interfacing the NES controllers to the GPIO this weekend, then I can start assembling everything.
I will have to move the mausberry switch to different GPIO pins because from what I have found, I will need the default ones for the controllers. This shouldn't be a big deal though.
I plan to post wiring diagrams of how i do this, if it works. I had a hard time finding simple diagrams, had to shuffle through a lot of info. Turns out (according to what I have read), it's not difficult to wire the controllers directly to the GPIO, but I shall see.

[brihyn]

I'm really going to be following this one, as the gpio solution is exactly what I have in mind, but don't want to do the research myself

[severdhed]

awesome.  i'm curious to see how the controls to gpio works out for you, i've thought of trying that for another project, but it may be a while before i start that one.

i'm strongly considering an NES pi project, mostly due to your projects....great job.

[pbj]

Still a hell of a lot easier to do this on a $20 Xbox....

[darthpaul]

I am just about to start ordering parts for my build, may I ask where you were able to find a NES case for $17.00?

[darthpaul]

Still a hell of a lot easier to do this on a $20 Xbox....

Maybe but it wouldn't have that 80s look or feel 

[DaOld Man]

I am just about to start ordering parts for my build, may I ask where you were able to find a NES case for $17.00?

I bought my first case from a user on here (not sure if these guys want me to mention names, but they can chime in if they want).
I posted on BST a while back that I was looking for one. The user said he had one and I scarfed it up.
The second one came from another user answering the same ad, but after I had already bought the first one.
When I decided to do another, I asked the second user if he still had it, and lucky for me he did.
I searched pawn shops and a flea market near me. The flea market had a booth set up for console games, he said he had half of an nes case but didnt know what happened to the rest. (Half is no good).
So you can check pawn shops, you might luck up.
Make sure it doesnt work, and you should be able to use that in your favor to bargain the price down a bit.
I will keep my eyes open, if I run across another I can buy it and ship to you, if you want it.
You may also want to post in BST on here.
I also searched ebay and craigslist, but not much luck. Ebay has some, but they claim they work and are pretty high. (Remember we need to salvage non working ones, if possible.)

[DaOld Man]

Update!
I have not had much time to work on this.
I have formatted and installed the retropi with emulation station on the sd card.
I have the original controllers "gerry rigged" into the GPIO pins, but have misplaced the code I need to download to test the controllers.
I have also ordered a gross of six (or is it four?) of those 2 pin panel mount high voltage plugs, and 1 cable to match.
They are supposed to be here early next week.

Hopefully I can find time tomorrow at work to find the code I need for the controllers, then maybe I can test them tomorrow night.
If I have success I will write up a quick tutorial how I did it.
I also have the NES switch/reset circuit modified (reversed polarity on the LED). I do have pics and will post how I did that too.

[DaOld Man]

Ok, I have pretty much given up on using the GPIO to interface to the original NES connectors.
All the code suggestions I have found do not work for me.
I have order a SNES to USB adapter. From what i gather from my research, the NES and SNES controllers are basically the same, electrical connection wise.
But if anyone can help me out by showing me the code I need to read the NES controller connected to GPIO, please tell me.

As promised, here is how I modified the LED on the NES power/reset switch assembly.
First, if you do not have a digital volt ohm milliammeter (DVOM), with a diode check function, you need to get one.
The diode check function can test an led, and even tell you what the voltage drop across the LED is, which can be very good when figuring the size resistor you need.

Here is a schematic diagram of how the NES power/reset circuit board is wired.
Left shows the polarity of the Power LED before my modifications, and the right shows the polarity after my modifications.
This drawing also shows the mausberry switch connections. (Sw+, SW-, Rst+, Rst-, LED)



Ok, first pic shows my DVOM connected to the NES switch white and orange wires.

You see the red lead of the DVOM is connected to the orange wire, black lead to the white wire. The red lead of the DVOM is positive, black is negative.
The DVOM is displaying 1.602. This tells me that the LED is forward biased and current is flowing through it. The reading is also telling me that the LED is dropping 1.602 volts.
You may not be able to see it in this pic, but the LED is faintly glowing.
This test also tells me that the orange wire connects to positive and the white to negative supply.
Since the orange wire connects to both the LED and the reset button, this needs to be negative.
We can change that by reversing the polarity of the LED.

If we reverse the DVOM leads, we see no voltage drop displayed on the meter, because the LED is reverse biased and no current flows through it.

This test confirms that the white wire is negative and orange wire is positive. However, we need orange to be negative and white positive, so to quote Hammerin Harry, "Let's get busy!"

Here is a closeup of the LED in its plastic holder. Yo can see the polarity of the LED is marked on the circuit board.


Now here comes the scary part. You must remove the LED from the plastic holder thinngy.
I used a knife between the rim of the LED and the plastic and gently pried it out.


Now we attach a heat sink to protect the led from the soldering gun that is heating up and getting ready.
You can see I used test leads on each of the LED leads. This will absorb most of the heat and protect the LED.


I now flip the board over, and using braided de-soldering wick, I place the wick between the first LED solder pad and place the soldering iron on top of the wick.
The heat will flow through the wick and melt the solder. The solder is then sucked up into the wick.

This takes a few attempts to get a clean hole, I always remove iron and let it cool for a few seconds before moving the wick to a clean spot and repeating. The cooling pause is to keep from overheating the LED.
When the hole is clean, I remove the iron for about a minute then repeat the process on the other LED lead.

After the LED leads are free, flip the board over and pull out the LED. The desolder wick I used is in background. Heatsink test clips are still attached to the LED.
You can also see the LED leads are bent 90 degrees.


Now I put the LED is a needle nose pliers (just about any pliers or clamp should work).


I then carefully bend the leads so the LED is 180 degrees opposite what it was.


I then re-insert the LED leads into the holes of the circuit board, and push the LED back into the plastic thinngy.
I also re=attach the heatsink test leads.
I then flip the board over.


And solder the leads back.


Now the board should be ready. The LED polarity should be reversed, and the orange wire should be negative.
We can test it by connecting the DVOM back to the white and orange wires.

And we can see that the orange wire is now negative and the white is positive. The voltage drop now reads 1.593. No big deal, this is not a real expensive meter.

No picture, but I did reverse the DVOM leads to double check.

So it should be ready to hook up the mausberry switch.

Please note that my meter reads 1. when it sees an over range voltage drop. (Same as open circuit). This does not mean 1 volt, it just means it doesnt see anything, or the volt drop is so high it cant read it. (Infinity).
Your meter may read something different when the LED is reversed biased. Some meters read OL. I have seen some that read --.
If your DVOM has diode check on it, and the leads are not connected to anything, the meter will display what it shows for infinity. Mine shows 1. when not connected to anything (on diode check).
As with all test tools, read the manual that came with it if you dont understand.
These meters with diode check functions are very useful. They can check LEDs, diodes, and even transistors.
Since we use LEDs a lot in this hobby, it should be put on your necessary tool list, if you dont already have one.

Of course, if you dont have a DVOM with diode check, and dont want to buy one, you can take my word for it and reverse the LED polarity without using a meter.

[Slippyblade]

Depending on which version of RetroPie you are using, the code is already there.  If you are using the new 3.0 version, all you need to do is activate the driver through the RetroPie setup script.  That's how I got mine working.

[DaOld Man]

Depending on which version of RetroPie you are using, the code is already there.  If you are using the new 3.0 version, all you need to do is activate the driver through the RetroPie setup script.  That's how I got mine working.

Remember, as far as Pi, I am about as smart as a dirty sock.
How do you activate the driver?

[Slippyblade]

I'll see if I can find the instructions again.  There are two drivers out there.  SNESDev is written by the guy who runs the RetroPie distro; it's designed to work with his GameBlock add-on.  Gamecon is a kernel level driver that expects to use raw inputs.  Gamecon is the one that I used on my SNES.

I'll also dig through the setup script again and see if I can find it.

[Draco_Elessar]

Awesome build! I used a USB adapter circuit to get the NES controller ports to work on my NESPC.

http://www.raphnet-tech.com/products/4nes4snes/

[DaOld Man]

Thanks Draco!
Yeah, after much trial and error, I have pretty much given up on using the GPIO to connect the NES controllers.
I think I got pretty close a few times, but I need to do more experimenting, and since I want to knock this project out, I decided to order
an adapter, similar to what you posted.
I ordered this one from amazon.com:
http://www.amazon.com/gp/product/B002IXZ5DE?keywords=snes%20to%20usb&qid=1444426847&ref_=sr_1_1&s=pc&sr=1-1

(Sorry about the long link).
If the link is broke, just search SNES USB adapter on amazon.com.
I have hooked both my NES controllers into this adapter and it works great. Pretty much plug and play and a whole lot simpler than
trying to use the GPIO.
However, I have not given up entirely and will pursue this avenue again if I decide to ever do another Pi build.
In the meantime, I am keeping my eyes open, just placing the GPIO to NES on the back burner for now.

Im at work right now but will post pics of the adapter and hookup diagrams later.

[DaOld Man]

Ok, here are a few more pics for your enlightenment and enjoyment.

First the wire colors of the SNES and NES connectors, and what each color does. (Also pin position on each connector).


Here is how the NES connector connects to the SNES connector on the SNES to USB adapter:

[JDFan]

Is there a reason you went with the SNES adapter instead of the NES to USB adapter if plugging in a NES controller ?? I just got one of the NES adapters the other day after finding my NES Advantage stick and have been replaying Zelda on my desktop PC the last few days ( Haven't played through it in a looong time and it just plays so much better on the old Advantage Stick I remember playing it on !!)

This is the one I bought  ( http://www.ebay.com/itm/191647755358?_trksid=p2057872.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT ) And like you said about the SNES one it's Plug and Play so makes it simple to use the old Advantage Joystick with the old Nes emulator in Win7.

[DaOld Man]

Good question.
I went with this one because from what I researched, it will work with NES or SNES controllers, since they both wire the same. (Of course it only has plugs for SNES).
This one also has two ports, so i can wire both the NES connectors to it.
It was either this or hack the original NES connectors to USB, like I did in my first Pi/NES project.
I wanted to keep it so I could use the original NES controllers, but plan to install extra USB plugs under the cartridge door, like I did on the last one, so I can plug USB SNES controllers in for other emulators.
For all practical purposes, unless you want to keep it as original as possible, I think it would probably be better to install USB plugs in the NES connectors, like I did on my first one.

[DaOld Man]

BTW, JD, Coursera has a course on programming in python, which can be used on the Pi.
I have signed up for it.

[DaOld Man]

Ok back to the NES switch circuit and the mausberry switch.
On my last build I added a 51 ohm resistor in the white wire going to the mausberry circuit from the NES switch.
This is perfectly ok, but I decided to install the resistor differently this time.
I put the resistor on the NES circuit board.
I removed a small section of the trace that runs between the LED and the Reset button. This trace connects to the orange wire.
I removed the copper with my bench grinder, very carefully I might add.
I scraped the insulating paint off the trace. I checked the trace with my ohm meter to insure the trace was broken.
I then bent the leads of a 75 ohm resistor (its the closest I had in the junk box), so that the resistor can sit on the board.


I then soldered the resistor across the gap in the trace I created earlier. (Sorry about blurry pic).


I then double checked with my meter to make sure I read 75 ohms between the orange wire and the LED trace.
I also checked surrounding traces to make sure I didnt short anything.
I then coated the resistor and the solder joints with hot glue, probably not necessary, but what the hey?

I then soldered the wires from the NES switch to the mausberry switch circuit.


I then connected it to the Pi, downloaded the needed script from mausberry.com, and it works great!

You dont have to add this resistor like I did. It will work fine if you just splice it into the white wire between the NES switch and the mausberry. (Like I did on my first Nes/Pi project)
This method puts the resistor in the orange wire, between the reset button and the led.
The led dont care where it is, as long as it is in series.
But if you mount the resistor off the NES switch circuit, it must go in the wire wire, and not in the orange.
If you placed it in the orange wire off the board, it would most likely interfere with the reset button function. (It might work fine, I dont know, didnt test it.)

This resistor may not be needed at all. Some chips regulate the current to the led so no dropping resistor is needed.
But I have no idea if the mausberry uses this type chip, so I figured why risk letting smoke out.

[JDFan]

BTW, JD, Coursera has a course on programming in python, which can be used on the Pi.
I have signed up for it.

Sounds interesting but just not sure if I have the spare time to keep with it. were you doing the one with University of Michigan (starts the 21st) or did you already start with the one with Rice (started Oct 3rd) ?

[DaOld Man]

Michigan.

[DaOld Man]

Almost finished with this project.
Just a little update.
Heres a pic of the hack job I did on the bottom half of the case.
I decided to mount the Network connector on the back of this one. Tried cutting out a square hole, it's ok I guess, but I think I should have just drilled a round hole like before.
I think the round hole looks better.
Left to right, cut out for HDMI plug, Ethernet plug, and two prong power entry.


Next pic is the Pi mounts and sdcard drop pan.
I cut out a couple of pieces from shiny black lexan, and drilled and tapped 4-40 bolt holes to mount the pi.
The tic tac case I used for the drop pan cracked when I was cutting it out, so I coated it all over with model cement.
Speaking of the model cement, it sucks.
I glued the Pi mount plastic pieces with hot glue and put a small pop rivet in each one, from the bottom. I dont think they are going anywhere.


I had planned on mounting this power supply just like I did the last one, but it was too big to fit the space. I thought I ordered the same PS, but evidently I up-sized it.
I used a piece of plastic, two plastic cable clamps, and a couple of wire ties to fasten the PS to a 4 existing bolt towers.


More pics to follow.

[DaOld Man]

More pics!!

Back shot with cables connected. You can also see Pi mounting, and PS mounting a little better.


Close up of the HDMI port:


Close up of the A/V RCA jacks. I more or less repeated what I did before.


Bird's eye view:


What else to do:
Cut out the panel that will mount behind the cartridge door.
Figure out how Im going to mount the SNES to USB adapter. (Not a lot of room left.)

[severdhed]

looking good.  its funny how quickly you can run out of space doing these things.  you look at that NES case and it looks so big compared to the pi, but once you start adding up all the adapters and cabling, it can get tricky.  I struggled fitting everyhing in my snes, i didn't even mount my pi, it just sits in there.  I also did an n64 (before i realized that the emulation wasn't quite where i'd like it to be)...that was a really tight fit.

i love this project...good job

[DaOld Man]

Thanks severdhed, that means a lot coming form the guy that did such a great job on the SNES!

Ive been thinking about a couple of things and would like some opinions.
I have the HDMI connected to a LCD monitor using a HDMI to DVI cable.
There is no speakers on the monitor, so I got no sound. I tried hooking the red and white rca AV plugs to my TV, and the sound comes through. (Video on the monitor, sound on TV speakers).
So Im wondering, should a mount a small audio jack beside the HDMI jack, to allow desktop speakers to be plugged in?
I could just parallel the audio jack with the audio RCA jacks.
Will the sound come through the DVI cable if the monitor has speakers built in?

Another thing I would like opinions on is the NES power led.
With that led wired to the mausberry switch circuit, when I turn off the switch the LED immediately goes out, even though the Pi is still shutting down.
Should I remove the white wire from the mausberry and attach it to GPIO pin 1, which has 3.3 volts until the Pi shuts completely down?
This would leave the led on until the Pi shuts down completely, signaling it is ok to unplug the power cord.
Or would it be just confusing, people thinking they didnt turn the switch off properly when the light stays on a few more seconds?

[severdhed]

DVI does not support audio, even though the cabling will carry the signal.  you can use an HDMI to DVI adapter, with a dvi cable, into another dvi to hdmi adapter, basically creating a hdmi cable and it will transmit audio just fine.  however i'm not aware of any monitors that support audio over dvi.  you would have to be using an hdmi input to get audio.

if you are planning on sticking with the dvi monitor, then i personally would add an audio jack in the rear,just so you don't need to run cables out the side of the case. 

as for the LED, thats a tough call.  are you planning on having other people unplugging your console?  even if the LED turns off immediately, the image will still be on the screen, indicating that it is still shutting down.   

in these situations, i can't help but feel that there isn't really a correct answer.  Ultimately, i know that I will now how to shut it down properly, but i don't really trust anyone else to do it right.    I didn't use a mousberry circuit, mainly because i'm cheap.  i just wired up my reset button to trigger a shutdown, then i turn off the switch once the unit shuts down.  one of these days, i have to show my kids how to make it work, but as it stands right now, i'm the only one that really uses it.

[DaOld Man]

Thanks severdhed, I guess if it needs to be done, I could use an stereo RCA plugs to mini jack adapter.

Almost done.
Cut out the USB panel today (this goes behind the cartridge door.)
Cut out the pane to mount 3 USB plugs. Since the SNES to USB adapter only takes 1 usb port,  I figured I needed to make the final USB port available and since I mounted the network port on the back, 3 usb ports would fit good on this panel.
I had some of that black shiny plastic left over from my last juke box project, so I cut the pieces out of that.


Test fitted into the case's cartridge slot:


I used hot glue to fasten the two panels, here is view from the front, with usb plugs mounted:


Here is a shot of the USB plugs glued in. I only ordered two of those USB cables, so I used the one I hacked up in my first frankenstein project. It was the one I was going to mount in the controller port hole, but didnt like the way it looked. Since it was hacked up, I had to use washers to fasten it, and I used a wire tie just in case.


And here is a shot of the SNES to USB adapter. I decided to leave the plastic case on, I was worried the circuit board could short out against something, since it is so crowded in there.
I used a "sticky back" attached to the case, and ran a wire tie around it and the usb and network plugs.
It looks like it is pretty solid.
I also used hot glue on the sticky back.
I still need to clean up the P1 controller wires, I got better fitting connectors for the SNES adapter pins on the way.


And here it is with keyboard, mouse, and two NES controllers plugged in.
I still got an extra USB port to plug in a mem stick on anything else I might need.
Can also plug in the USB SNES controllers to play other emuls that need more than two buttons.


Now im thinking, what should I put on the door? I used Pi-tendo on the last one, dont really want to do that again.

[reptileink]

I would just leave the door as it is, but if you insist on changing it:

NinPIdo
Entertainment System

[DaOld Man]

I would just leave the door as it is..

That option is not off the table.

Thanks for your input.

[severdhed]

looks awesome.  that usb port panel looks really good.

[DaOld Man]

Thanks severdhed!!

Just a quick bump to say this project is pretty much done.
I have ordered some cheap heatsinks mostly because I just dont feel right not having a heatsink on the CPU (Its not getting that hot but my old PC experiences are haunting me.)
They were cheap, but on a slow boat from China.
I will post pics when that is finished and complete this project.
I currently have it plugged into a monitor, using a HDMI to DVI cable.
I wanted sound too, so I threw together a RCA jacks to 3.5 MM plug. Got some PC desktop speakers plugged in and I must say it sounds good.
So if anyone decides to use the Pi in a "regular" arcade cabinet, you might want to go this route. HDMI to DVI video to the monitor and use the AV jack on the Pi to get the audio for your speakers.
Here is a pic of my home made RCA to 3.5 MM audio jack adapter: