@ kevtris: download the source code of my "FunnyMu Unofficial" from the website. There's an useful "instant load/save" routine, written in C, which you can use to understand the specifics about loading/saving from/to cassette tape. ;) Actually I looked through the source a bit earlier and didn't fi...

Thanks for the video links and the logo BIOS! Looks like the sound and video on my doodad is matching your videos, so that's good. I did some testing and all the games do seem to run fine in PAL or NTSC mode, without too much in the way of speed variations. To finish things up, I finally implemented...

The graphics disappearing is normal too! Quality control obviously slept through those ;) Also you'll find the sound stops in Crazy Chicken, and that's normal too. Fortunately, mobsie posted some video of those running on a real CV, so you're fine. Maybe it's different in FPGA, but using RESET in a...

Aah, so they did use NMI. I just use reset though because NMI and reset both point to the same vector, so there's not much difference. Well, depends on your point of view. To the 6502 the two are fundamentally different. From the MOS manual On a RESET, the CPU loads the vector from $FFFC/$FFFD into...

This is normal for most games. The RESET button just forces an NMI, which on re-entry, tells the game to go to GAME TYPE selection. The no logo is also normal for a non Creativision console. I guess it was cheaper just to blank the logo than re-write the BIOS. I've attached my BIOS disassembly, I u...

Thanks for those docs, the schematics were helpful. There's a page missing though; the page with the sound chip and 6821. I have some edge cases I found, like what happens if you read the write port or write to the read port on the VDP. (Reading 3xxx will cause the VDP to latch open bus data; writin...

MADrigal wrote:I tried to send you emails yesterday, but they were rejected by your spam filter.

I have docs to send you such as data sheets, memory maps, etc.

Sorry about that. I will pm you an alternate email address you can try. My ISP is a pain about its spam filter, unfortunately.

Hello, welcome to the forum! :) There's no PAL and NTSC games. They're "multi-standard". Same exact ROM program. NTSC and PAL CreatiVision's differ in the VDP only: TMS9929 for PAL, and TMS9918 for NTSC. BIOSes are also the same in Japanese and European/Asian units. I dumped and compared them mysel...

As it says on the tin, does a comprehensive technical document exist? I did a fairly through search of the forums and the internet in general and cannot find a document about the guts of the system. Be this as it may, I think I have reverse engineered most of how it works from a disassembly of the B...

Hey everyone. I'm currently thinking of adding Creativision to my FPGA videogame system, and thought I'd poke around a bit on the forum and confirm a few things to see if I understand everything. Because I'm in the US, I will be making an NTSC Creativision first and will most likely back port it lat...