SpritesMind.Net

WOW! Thank you so much for doing this!
The pcb calls the two gals "PAL16L8" even if they used lattice gal parts... if you can figure out which pins are inputs and outputs (which can vary based on the fusemap) it should be possible to brute force a truth table out of those parts, even if they are ...

Thanks so much!
Did you ever end up doing high-res scans of the front and back ROM/RAM carts? I'm trying to figure out the memory map of the carts, and I can't read the 74xx chip labels on the pictures at http://www.tmeeco.eu/FileDen/GEMSstuff.jpg
I know from the GEMS 2.8 program that at 0x19f8 it ...

TmEE co.(TM), is there a chance you have the schematic for the parallel port to EXT adapter available somewhere? I'd like to breadboard one myself. I'm also curious what the memory map for the ROM/RAM carts is (and what the 4 dipswitches do).

I'm trying to throw together a working GEMS setup ...

http://nesdev.parodius.com/bbs/viewtopic.php?t=5887
Kevtris writes:
"Wellll, since no one had made one, I decided to. I came up with a new SMS/GG/CV ripped music format I called SGC. Unlike most of these things I got some rips to back it up.

I ripped no less than 365 sets of music from various ...

What happened with this? Did the weird stuff get documented? Eke, did you manage to fix the core?

LN

BTW, could the differences on those graphs on the prior page, between the ym2612 and the sega asic version, be because the sega asic one has the 'off by one' error on the descending portion of the sine wave fixed?

LN

Ok, even if I don't understand the exact importance of them, those images look DAMN cool!

Wouldn't they look identical between MD1 and MD2 if both were sampled at the same rate? Does the samplerate have a large effect on those images? Does anyone have a ym3438/opn2c to compare to the opn2 in the ...

YM2612/YM3438 are not the only chips which do time-multiplexing of the output channels rather than using a 'real' accumulator to mix them (the 3438 DOES use multiplexing, right?):
The YM2413 OPLL and the Konami VRC7 (which is a reduced-ym2413-on-a-famicom-mapper-chip, almost certainly manufactured ...

I did top-illumination using a 1940's binocular scope (my mom used it in medical school in the 1970s) by taking one eyepiece lens out and sticking a flashlight in the hole (being sure it didn't fall in and scratch something). It DOES work, but only so-so; you get a lot of light from the second eye ...

opl2 rom3:
This decoding is based on http://yehar.com/adlib/ym3812_rom3_1.jpg
Legend:
0 = dark/absent gate, 1 = light/present gate
C = clear/correct for this address, C? = probably correct.
X = a pullup or perhaps pulldown between every 2nd rom line,
only present on bits which need it. This was ...

Two questions: was the minor fix to fm.c (ym2203_emu.cpp in tfmmaker):
** 14-02-2006 Alone Coder:
** - fixed YM2203 stop volume (511 instead of MAX_ATT_INDEX) - verified on real chip
** - fixed YM2203 SSG-EG=#0a key off (inversion disabled) - verified on real chip
** - uncommented sine generator in ...

I got the high-res opl2 pics from Olli (he goes by 'yehar' on ircnet), and unfortunately, not all the chip is imaged at high res. There is also at least one smaller rom on it (roughly 16x7 bits), which could be key-shift or other LUT tables which are not imaged at a high enough resolution yet to be ...

ouch. whoever owned that megapc snapped capacitor c113 off of the MD isa card. SOMETHING is gonna work completely wrong until that is replaced.
EDIT: nope, once again I'm wrong. C113 is NOT SUPPOSED to be populated. see a later megapc plus card here: http://aycu14.webshots.com/image/27693 ...

I've updated the post above with the systems list with tmee's corrections, and to include late MD2 and MD3. Please add comments.

Also, which MD2 has the z80 inside the giant asic? VA4?
Thanks to tmee's correction, I know all the va1.x ssytems are really 'VA1' systems regardless of the second number ...

In response to ym2612 versions, there appear to be 7 variants of the MD system *in terms of ym2612 and VDP*:
MD1 VA0 thru VA6: use a real yamaha ym2612 and a real 315-5313 VDP (note that va0 and va4 (and likely the intervening models, but please correct me) have 3 asics, while at least va5 and va6 ...