N64HHv2: Silver-Undervolt and MGC-Green Editions

CrazyGadget

Crazy Helpful, CrazyGadget
.
Joined
Jun 6, 2020
Messages
612
Likes
882
Location
Downing's Closet
Portables
???
20240416_182315.jpg

20240416_182512.jpg
20240416_182524.jpg


A couple of months ago, the MGC crew decided that we wanted to build one of @Nicholas298's sexy N64HHv2s. Being that I already had most of the parts, I was more than willing to bring a kit with me to MGC. That being said, no one attending (myself included) had ever built an N64HH, so I wanted to do a "dry fit" test run to get an idea of how it all went together. That blossomed into wanting to build one to surprise everyone at MGC (and to get a better idea of the build process as to not waste time at MGC). That blossomed into me whipping up two more kits and trucking to @Gman's house the weekend before MGC. We spent about 3 hours just staring at everything and trying to figure out how it all went together.

20240331_002826.jpg


At the end of the evening, we didn't make all that much progress on either of our builds, but we saw the vision...
Over the course of the following week, we both worked on our respective builds, with Gunnar finishing his well before I finished mine. In that time, I got a package in the mail with some RCP breakout flexes I made, as to eliminate the need for direct RCP wiring (thank you @atkfromabove for the inspiration!). I also hooked my PMS Lite up to a Wii to configure the charging current and LED mode.

20240402_222321.jpg
20240403_212150.jpg
20240404_131742.jpg


It came down to the line and I ended up staying up almost the whole evening before my flight wrapping it up. Unfortunately, I had to call it a night with the portable not having any audio. While I was getting ready for my flight in the morning, I realized that I forgot to short HS to ground on the 64Amp, and popped open the portable to fix it with minutes to spare before I had to rush to the airport (maybe that's why I forgot to bring underwear to MGC lol).

20240404_201237.jpg
20240404_221558.jpg
20240405_045744.jpg


Unfortunately, while my joy stick would move down and right, I would get no response from up or left, despite running the stick configuration multiple times. It ended up being some borked code on the joystick converter, and I was able to fix it when I got home from MGC (Thank you Gunnar!). Speaking of MGC and Gunnar, he pretty much built the whole green HH at MGC (I also believe @Benge did all the wiring for the front half). There are a bunch of pics already in the MGC thread, so I'll just leave this beauty shot here.

20240406_232726.jpg


Post MGC, I was eager to wrap up both portables. As mentioned above, I reflashed the PIC for the joystick converter in the silver HH and verified it was working as it should. I also wanted to change the twisted-magnet-wire-over-FFC composite line with a straight-shot shielded wire between the N64 and the screen driver board. However, my eagerness to wrap up the build got the best of me, and instead of soldering the shield to ground on the N64, I soldered it right to the 5V plane and.... poof!

20240410_171114.jpg


Looking back, it was pretty comical to see the magic smoke come out of the top vent of the HH. At the time, though... not as funny. Anyway, Gunnar hooked me up with some part numbers, and I patiently awaited a Digi-Key package. In the meantime, I swapped the composite line in the green HH for shielded wire (soldering both shields to ground this time), fixed the joystick FW, and wired up the volume controller board, bringing that portable to a close. I've been playing Paper Mario on it and this portable is awesome!!! Definitely be weary of printing that back plate in PLA though, the one in the green HH is quite warped now after ~20 hours of gameplay.

20240411_162834.jpg


While I waited for my package, I decided to experiment with undervolting in the silver HH. Using my bench PSU, I slowly dropped down my 3v3 line until I noticed instabilities, either in the N64 itself or from the peripherals. While the N64 can go quite low (around 2.6 or 2.7V), the 64Amp wouldn't give me any sound at 2.8V or less. I found that 2.9V was the sweet spot for everything, with both OEM and flash carts working, sound working, controller working... it all seems good (for now). As per @Wesk's experiments, it's about a 1W savings (5.25W vs 4.25W). With the 5V rail drawing 2.2W for the screen / N64 video DAC, this means we have an overall 13% decrease in power!

One Digi-Key later, I swapped out the whole 5V section of the board for fresh components, and I used some resistors from my sample book to change the 1v15 reg to spit out 2.9V. @Aurelio was also kind enough to modify the PMS's FW to change the battery cutoff voltage from 3v3 to 2.9V, so I should get even more juice out of this setup. Wired it all back up in the portable, and voilà!

20240415_221626.jpg
20240415_221609.jpg
20240416_181043.jpg


That's pretty much where the story ends (for now), and I don't really have any more glamor shots, so here's a weight comparison between the two:

20240416_182645.jpg
20240416_182657.jpg


Thanks for reading!​
 

Attachments

Benge

.
Joined
May 18, 2020
Messages
203
Likes
694
Location
France
Portables
4 : O-Wii (V1,V2,V2.1)/ BS2
Nice build, I was happy to help with the soldering of some magnet wire for the controller :)
I hope to see an upgraded version of the PCB with FFC connector.

I really like the grip of this design, maybe I'll build one in the futur
 
Joined
Dec 11, 2022
Messages
42
Likes
67
Location
Texas
Portables
5
Awesome builds! All the internal shots are helpful for those of us just not jumping into this design
 
Top