• Ordering from the BitBuilt Store will be disabled until sometime next week. We apologize for the inconvience!

Worklog PPR

Joined
Jun 4, 2016
Messages
17
Likes
14
Wow I still remember a long time ago when I first found your WIP. Amazing work!
 

Miceeno

.
.
Joined
Nov 30, 2016
Messages
118
Likes
198
Portables
4
This is so goddamn beautiful it brings tears my eyes.
 
Joined
Dec 28, 2016
Messages
101
Likes
795
For some reason it's booting but the bootloader hangs. This is the same phenomenon as the 3x3 board (it worked with 64drive HW2 but not real games or 64drive HW1). the VGA part is perfect though - it just works.
 

Miceeno

.
.
Joined
Nov 30, 2016
Messages
118
Likes
198
Portables
4
I'm not going to pretend to know what I'm talking about on this matter but do you think there's an issue with the security chips? Is it possible that on the smaller board the distance between the CIC and PIF is shorter thus causing a timing issue on the security checks before boot?
 
Joined
Dec 28, 2016
Messages
101
Likes
795
Ok, today I spent 10 hours debugging all my problems.


1. The first two boards have pulldowns on /INT1 because my documentation did not show the correct notation, so I thougth it was active high. Changed to pullup and all games started working, real carts, all 64drives etc. 64drive HW2 managed to work even without this because the relatively weak pullups on the cart brought the signal above logic 1 threshold. If the line is stuck low as it was, it would spam the game with interrupt signals and the handler woudl basically spend 99% of the time servicing the interrupt.

2. Same thing on the combined board, but I found that the Rambus Vterm regulator was going into hysteresis, a sawtooth with 0.4V ripple. Since the frequency was 15khz I could even hear it. I foud that because the bulk bypass cap on Vterm was too big for the footprint, it wasn't even touching GND. Fixed, and it booted its onboard 64drive!



Power draw is around 0.56A @ 12V, so about 6-7 watts. Not bad!

 
Last edited:

Bakuku

.
Joined
Jul 23, 2016
Messages
211
Likes
115
Location
Genk
Portables
4
Looks amazing! As it is now, it will still require a small heatsink, right?
 

Bakuku

.
Joined
Jul 23, 2016
Messages
211
Likes
115
Location
Genk
Portables
4
Yeah, it's still the same chips as in a N64, just a better board.
With all the components so close to each other, wouldn't the board produce more heat? Or are all components aside from the chips replaced with better alternatives?
 

Shank

Moderator
Staff member
.
.
.
Joined
Jan 31, 2016
Messages
1,108
Likes
2,127
Portables
4
With all the components so close to each other, wouldn't the board produce more heat? Or are all components aside from the chips replaced with better alternatives?
He literally posted an annotated thermal image of the board's thermal performance. Its topping out at 68.4C in a non-enclosed environment. Yes, it needs a heatsink, just like every other N64 portable.
 
Top