Did some more investigation into the PAL N64's RGB output or lack of it...
What I found was that my suspicions were correct. The first 8 or 9 pins on the DENC appear the video bus. They carry the RGB signal (presumably interleaved) from the RCP. What is needed is a small circuit with three latches. This would capture and seperate the red, green and blue signals, so they could be fed into an external encoder.
What we'd effectively end up doing is building our own DENC. I'm not sure how the sync signals are generated, but they appear to come across the video bus too!
Can't wait for more developments.....
This mod would be fantastic
Pete
Well, I've ordered myself a logic analyser, so I can see what actually happens on that video bus. Hopefully it'll turn up in the next few days, so that I can get to work on reverse engineering what's going on.
Hi Aidan,
Mind telling what analyser and where you bought it? I've been looking for one but haven't found a cheap enough one for my limited budget.
Anyways, I'm looking forward to seeing your results.
Hi David,
The logic analyser is a PC based one, and has a limited bit width and word depth (3076 words of 8 channels). I can't really justify anything more expensive, as it's not going to get a great deal of use. I nearly threw something together using a couple of FIFOs and the parallel port, but decided it wasn't worth the effort or the cost of buying the FIFOs.
There are several PC based ones that don't look too expensive, for example look at USB instruments (http://www.usb-instruments.com/) or USBee (http://www.usbee.com/).
I'll let you know how this one works out. USB Instruments also do a 16 channel version.
Edit: The device turned up at home about ten minutes after I'd left for work...
Well, I've hooked everything up, and monitored what's going on. Not a lot of it makes much sense yet, but that's hardly surprising. I've taken a trace of a blank screen. This was obtained by starting the system up, resetting the system, and then crashing the processor. This provided a nice blank screen with sync pulses.
If you download the software from http://www.usb-instruments.com/files/ANT8setup.zip (http://www.usb-instruments.com/files/ANT8setup.zip) you can then load the trace in. The sample rate was 250MHz. The trace is attached.
Config:
chan pin
0 - 11
1 - 2
2 - 3
3 - 4
4 - 5
5 - 6
6 - 7
7 - 9
Double You in germany is the company, which made the PAL N64 RGB Mod 1997. Unfortunately, all RGB Modchips and diagrams sold to www.wolfsoft.de
If you like get more infos, you can contact double you:
info@double-you.de
www.double-you.de
I`m sure those can also understand english language :)
Bye Markus
had any progress? i have an rgb cable just waiting to be used but an n64 without the ability to use it
come give some news about N64 model who support RGB.
I recently see a new PAL model with year 1997 on motherboard.
This model is diferent. It has a VDC chip on it, not DENC. But near (at right) the DENC chip, it has a new IC (U5) called :
- "S-RGB A"
- "BA6596F"
- "732 160"
This is a 24 pin chip.
A strange other thing :
This model has a "1997" motherboard and serial number is : NUP11796059
My original N64 has a "1996" motherboard and serial nuber : NUP14026320
I don't find any datasheet about pinout of S-RGB A chip. If someone know about pinout post here !
BA is the part code for ROHM chips, they're usually the company that supplies video encoders to Nintendo (they did for the SNES). Unfortunately it's almost certainly a custom chip, and there are no pinouts available that I've seen. A search for the part number brings up nothing more than the usual bunch of asshole 'suprlus parts!' dealers with nothing but massive lists of part numbers and a request for money to access their database.