Do we have room for another N64P? (t64 WIP)

[kibble]

Hi guys! New to the forum here. I was inspired by many of the things I saw on here to build my own N64p.

I currently have many of the parts I need but, I still need a screen and some other misc things. I have taken lots of pics of what I'm working with so far but, I have to resize them and upload them.

My goal for this project is to make it as small as possible and I want it to have the following features: Built in Rumble pak, built in 1Mb ram for saving games (the N64 can address 32K only so it'll be like having 4 memory cards built in), 8MB RAM for full expansion pack capability, heatpipes with temp controlled fan(s) to cool the CPU/RCP/RAMBUS chips, PSP style analog stick, a small "subwoofer" for reproducing low frequency audio so it sounds richer and not so "tinny", and I want it all to fit in a vac-formed case which I want to be no thicker than 1.5", not including the cartridge input. I will be using lot's of SMD components to keep everything as small as possible.

I will be building all my own circuit boards including the N64 mainboard, which will be a double sided board containing the CPU, RCP and two 36Mb RAMBUS chips. Cutting the already built N64 mainboard just wasn't an option (too big). The boards will have mating headers on them to connect the various parts within the device directly together, where possible, so they can be "sandwiched" and take up little space. This means no using wires all over the place to interconnect things.

Just for the record, no, I don't have specialized equipment to built all of this and yes I know that it's a major challenge. With that said, I have home-built plenty of circuit boards and I just keep pushing myself to build something better and smaller. I build everything in my garage with stuff that can be purchased pretty much anywhere. Speaking of which, I will also need to build a vacuum forming machine (I've never vacuum formed before either ).

So there, that's my intro. Pics and video will come soon!

[argelfraster]

That sounds like a really hard project. Why not start with a regular n64p? i mean re-doing the motherboard and whatnot will be super hard, but if you can accomplish this you have the make a guide! Ill be watching your progress.
Good luck.

[kibble]

That sounds like a really hard project. Why not start with a regular n64p? i mean re-doing the motherboard and whatnot will be super hard, but if you can accomplish this you have the make a guide! Ill be watching your progress.
Good luck.

Thanks! I have two other N64's though that I am using as reference to build the board from scratch so if something doesn't work, I can use one of the working ones to see what's going on. 90% of the time, my stuff works...the other 10% blows up.

Here's some pics.

These are some of the components I will be using:



The SMPS I'm using was removed from a laptop. It contains both 3.3 and 5V regulators and can be turned on/shutdown with two pins.





This is a Ti PTN78020WAH regulator that I was originally planning on using instead of the 3.3/5V one but, I'm probably not going to use it for this project now.



This donor N64 contains the AVDC-NUS Audio/Video DAC.



I'm going to use two, 36Mbit RAMBUS chips but, I still need to get my hands on another expansion pack for the second 36Mbit chip.



I was going to use the two, 18Mbit chips and one 36Mbit chip but, that would be counter productive.



This is after removing all major connectors from the board.



and bottom.



This is after removing the DAC, PIF and quad buffer.



This is after removing everything else.



And last but not least, these are all the chips after being removed.

[dragonhead]

if you get a good board design built, consider publishing the eagle files so others can make and populate their own boards.

[marshallh]

Nice job so far. I know a couple people have made schematics already, some incomplete though.

While you can do it on a 2 layer PCB, you won't be able to shrink it down very much past what it is now. You need to go 4-layer to get it down much further.

[kibble]

While you can do it on a 2 layer PCB, you won't be able to shrink it down very much past what it is now. You need to go 4-layer to get it down much further.

Ah, but therein lies the challenge! Plus I have a few tricks up my sleeve, stay tuned!

[icarus]

I'm really excited to see how far you can shrink it down. I don't know much about PCBs, but it is interesting to think how it could affect future N64 portables.

Good luck!

[eagle5953]

While you can do it on a 2 layer PCB, you won't be able to shrink it down very much past what it is now. You need to go 4-layer to get it down much further.

True, but he could still come up with a shape that's "better," if not a good deal smaller. I think a rectangle (or better yet, a rounded rectangle) would yield a board that works better for our purposes than the square of the N64 board.

Are you planning on building in the power adjustment? If you only needed to supply power to one spot on the board and it took it from there, that would be ideal, no?

[marshallh]

I'm assuming that you are comparing to a cut-down N64 board - which is about 12 by 9 cm.


Either way, keep us updated.

[eagle5953]

Exactly. The 12cm by 9cm board could be a rounded 16cm by 7cm, for example, without being any more dense.

Additionally, if he's redoing the entire board, there's no reason he couldn't make it in two pieces that connect with a length of ribbon cable for easy folding (a la Bacteria's attempt), right? That would allow for an N64 portable with a considerably smaller footprint.

[kibble]

Are you planning on building in the power adjustment? If you only needed to supply power to one spot on the board and it took it from there, that would be ideal, no?

I thought about building the 3.3V regulator on board using a LM2596 switching regulator with required inductor and diode. It's supposed to handle up to 3.0A of current, which should be sufficient however, I did notice that there's 5V going into the AVDC-NUS IC. I supposed I could build a tiny boost regulator right next to the AVDC so that it receives the power it needs at that one pin from the surrounding 3.3V. That would cut down on the size even more and eliminate having to run multiple power lines to different areas of the board. I only want power from the batteries entering one section of the board and I don't want to use linear regulators other than the one used to get 2.5V for the RDRAM.

The only other power related concern I have is that I'm supposed to get a screen from one of my brothers and I don't know what the power requirements are for it or how big it actually is. It's a screen for a PS2 slim.

Up to now I've been trying to collect as much information as I can about how the board is wired so I can see what can be eliminated and what needs to be kept. I'm already planning on eliminating the AMP-NUS IC and replacing it with an 8 pin amplifier as apparently the AMP-NUS IC is only used as an amplifier for audio coming from the DAC and audio mixer for analog audio coming from the cartridge, which I know no games that use it.

[kibble]

Here's a teaser pic of what I got going as of right now, I want the total size of the board not to exceed the real estate needed by the major components by much.



Before you start critiquing it, just know it's FAR from done, all I've done so far is placed some of the components and run some of the connections between them so I can compare with the actual N64 board. I have yet to space out the traces evenly and shape the traces so they fit in better, throw in some grounds, add the bottom layer and all other components, etc, etc and whatnot. It's taken me hours just to get this far.

[nevermind1534]

You should get some extra PCBs made and sell them. I would definitely want to buy at least one.

[argelfraster]

You should get some extra PCBs made and sell them. I would definitely want to buy at least one.

Seconded.
Or at least a guide.

[nevermind1534]

Or at least a guide.

The file with the layout.