Last few days I was on a quest to find RGB signal from my CDi 450. It uses custom Bt9106KPJ video encoder and google doesn't know much about it :/. I didn't found any RGB, but S-Video is there: High resolution: http://www.cockroachrun.com/files/links/cdi/philips_cdi_450_s-video.png Well, I kinda admit it's a crappy console but maybe this information will be useful to somebody.
Yeah, I've noticed that Bt encoder is used in 3DO console also. I bought 3DO RGB kit from Otakus yesterday and also I got some schematics, will try to look into this, maybe I will be able to use same approach for CDi. These encoder shouldn't be very different, input pins should be the same: 8x3 matrix (8 bits per each color)
So one thing rather interesting about an alternative Brooktree DVE chip (bt856) is that the datasheet here: http://mjpeg.sourceforge.net/driver-zoran/datasheets/bt856.pdf references the output pins for RGB as available but shared with Y/C/CVBS. Pins 2, 4, 6, 8 are RGB and CVBS respectively when pin 10 is high and CBVS, CBVS, C, Y when pin 10 is low. It is a stab in the dark, but I wonder if pin 10 on the Bt9106KPJ is currently low and if you get the same CBVS signal from pins 2 and 4. The fact you found C and Y on pins 6 and 8 REALLY has me curious as that would also line up with the analog output circuit of the bt856.
That's very interesting find, and it would be a very elegant solution to do if pin 10 controls the mode. I may try that later once I'll sort out my other activities. Other than that those BT chips accept RGB bit matrix as the input so the chip can be replaced with Altera which will generate proper RGB (or analog approach which was used in 3DO RGB mod, some French web store is selling that for a premium, forgot the name).
I've tried this today and it doesn't switch the mode :/ (by default pin 10 was floating). Other than that the IC really looks like BT856, VAA and GND are on the same spots and so are the RGB matrix pins. RetroRGB has sent me CDi 210 PCB photos. That console has SCART output and BT9107KPJ. I think I'm missing something here. There definitely should be a way to switch to RGB mode.
Ok, more findings: 1. All VAA and GND pins in BT856 and BT9106 are compatible 2. Pin 44 - +5V 3. Pin 45 - HSYNC 4. Pin 46 - VSYNC 5. Pins 62, 63, 64 are +2V and I suppose they are FS_ADJUST, VREF_IN and VREF_OUT EDIT: Pixel arrays: Pins 17,18,19,20,23,24,25,26 - Red? [0..7] Pins 27,28,29,30,31,32,33,34 - Blue? [0..7] Pins 35,36,37,38,39,40,41,42 - Green? [0..7]
Darn. So I wonder if pin 10 is just not used in this package...Otherwise, as you stated, things seem quite similar...
So here's the thing: retrorgb has sent me the photos of CDi 210 which RGB capable through SCART output and BT9107 is used. I'll have such console here soon and I'll check everything with oscilloscope. Will report my findings here.
