second batch of ma-20 cartridge

Master (190)

11-01-2018, 01:34

I'm making a second batch of the ma-20 cartridge.
There is still time for anyone who wants to sign up for this new batch.
characteristics:
512k of mapper
V9958 (but the rom is msx 2.0)
3-video outputs: vga (15khz), s-video and composite video
1-slot connector (expanded)
obs:
most games only work with loader: sofarun
95% of games played normally

interested email to me:
fzanoto@yahoo.com

By fzanoto

Master (190)

11-01-2018, 02:56

funcionamento:
https://youtu.be/sXVlFOhdQBk

By fzanoto

Master (190)

11-01-2018, 13:00

his value is 350 BRL
the freight is around 45 USD
the vga output is only 15khz and needs dedicated monitor
Yes, the video responds on ports # 88 and # 98
the rom can be replaced, but it is a very difficult process.
does not have f4, nor rtc.
the sub-slot is for you to plug a game cartridge or fm.

By fzanoto

Master (190)

11-01-2018, 13:12

Attention:
I do not have the prompt delivery, I'm putting together a new batch and it can take several months for this entire process to be completed.

By Robby

Master (219)

12-01-2018, 11:10

Hi,
The MA-20 unit can be used without any msx(1) modifications, as i can see in https://www.msx.org/forum/msx-talk/hardware/ma-20-clone-msx2...

I have one remaining question:
-As far is i know, the original v9918 msx1 chip is using the ports 98h and 99h. Doesn't this results in a conflict on the i/o bus?

RJ.

By gdx

Enlighted (6436)

12-01-2018, 13:04

fzanoto wrote:

the rom can be replaced, but it is a very difficult process.

Is it a Japanese, international or other ROM?

By sd_snatcher

Prophet (3675)

13-01-2018, 01:00

I'm not related with the project, but given the language barrier I'll try to help to answer some questions.

- The cartridge is an improved NEOS MA-20 clone with the V9958 VDP
- It can be used to upgrade an MSX1 to MSX2 (and MSX2+ if the BIOS is updated) without any modification to the computer
- The games must respect the MSX coding guidelines to work with the cartridge. The majority of the Japanese games they tested worked fine.
- It uses the same BIOS as the original NEOS MA-20
- The BIOS is saved in a Flash chip. This means other versions of the BIOS can be flashed to update it, or to change the region/keyboard layout.

By gdx

Enlighted (6436)

13-01-2018, 01:55

sd_snatcher wrote:

It can be used to upgrade an MSX1 to MSX2 (and MSX2+ if the BIOS is updated) without any modification to the computer

This is not true for MSX2+ software because this expansion is removed from standard since. Probably all MSX2+ software access directly to VDP via 98h~9Bh ports . I think fzanoto used the V9958 only because the v9938 is harder to find.

By sd_snatcher

Prophet (3675)

13-01-2018, 13:49

Quote:

because this expansion is removed from standard since.

I see this being repeated from time to time, but are there any official references citing that? At least the MSX Datapack states that it's mandatory to always use the I/O ports pointed by the BIOS.

By sd_snatcher

Prophet (3675)

13-01-2018, 13:54

BTW, how many MA-20 cartridges did you sell in the 1st batch, fzanoto?

By iamweasel2

Paladin (722)

13-01-2018, 19:31

gdx wrote:

sd_snatcher wrote:

It can be used to upgrade an MSX1 to MSX2 (and MSX2+ if the BIOS is updated) without any modification to the computer

How many MSX2+ softwares are we talking about? I believe there aren't many of them. The good ones can be patched to work with MA-20.