Make your own MSX-on-a-chip! | MSX Resource Center (Page 2/4)

By flyguille

Prophet (3028)

30-05-2005, 16:19

is fast enought the ram memory of 1CM to get more than 16 sprites in one line?

By flyguille

Prophet (3028)

30-05-2005, 16:21

remember that the only one limitation for sprites is the memory speed.
ideed all the limitations of the vdp is about memory speed problems.

By [D-Tail]

Ascended (8258)

30-05-2005, 22:20

--  constant SpMode1_nSprites: integer := 4;
--  constant SpMode2_nSprites: integer := 8;

and:X MUHAHAHAHAHAHA!!!!!!!!!!!!!! :XYou're a real mean guy

By Sonic_aka_T

Enlighted (4130)

30-05-2005, 22:34

bad idea? okay, we'll leave it at 4 and 8 then!

By dhau

Paragon (1570)

31-05-2005, 16:11

Why would one put the Z80 in fpga?
The Z80 is still on the market and will presumably continue to be available at reasonable cost.
By not having the Z80 in fpga one can save a lot of gates for other purposes
and I think changeableness of the CPU is not really important for most people.
I'd rather have an msx2 compatible two chip msx than a one chip msx compatible with MSXA's one chip MSX.

1) Speed
2) Core voltage

It costs cheaper to get extra 20k or so macrocells on FPGA chips then use buffers to corelate 3.3/5v and 1.8v between ancient CMOS/nMOS garbage and modern FPGA

By arnold_m

Master (173)

31-05-2005, 17:05

Why would one put the Z80 in fpga?
[...]

1) Speed
2) Core voltage

It costs cheaper to get extra 20k or so macrocells on FPGA chips then use buffers to corelate 3.3/5v and 1.8v between ancient CMOS/nMOS garbage and modern FPGA
Good point, I was not aware that z80 and fpga use different voltages.
To put things in perspective, how many cells does the current ocm have, and how many are needed for the z80?

By snout

Ascended (15184)

31-05-2005, 17:06

arnold: check rite here ;)

By flyguille

Prophet (3028)

31-05-2005, 17:21

the one in 1CM has 12k of cells (LEs)

the best z80 emulation that uses already 4k, the vdp uses more than 4k (maybe 5k), so only left 4k for PSG and MSX engine

maybe is 2 1/2 k LEs for improvements (enought for one simple chip emulation like a sound chip)

important note: that was a conclusion seing the files already posted in this thread, maybe the compiled version that comes with 1CM differs.

EDITED

By AuroraMSX

Paragon (1902)

01-06-2005, 09:12

the one in 1CM has 12k of cells (LEs)

the best z80 emulation that uses already 4k, the vdp uses more than 4k (maybe 5k), so only left 4k for PSG and MSX engine

maybe is 2 1/2 k LEs for improvements (enought for one simple chip emulation like a sound chip)

important note: that was a conclusion seing the files already posted in this thread, maybe the compiled version that comes with 1CM differs.

EDITED

So, if we want to have full R800 and V9958 support, plus SCC+ and FM-PAC and MSX-AUDIO and MSX-MIDI and MoonSound and Gfx9000 emulation on the 1CM, it's going to be an 2CM or even 3CM?

By wolf_

Ambassador_ (9950)

01-06-2005, 11:29

Or in short: all the arguments related to 'upgrade the 1cm yourself' aren't really that special, for the simple reason there's not enough power. Perhaps some extras for the msx1, perhaps msx2 and little bit more, but not really something that makes the 1cm interesting for the current scene of users who already have a good expanded msx2(+/tR), unless they like the gadget-value, the connectors, and the RAM (as far as 32mb is relevant for MSX1 stuff, current msxdev'05 rules state 1024 times less RAM ).

2ct.