Hidden MSX hardware

Page 12/14
5 | 6 | 7 | 8 | 9 | 10 | 11 | | 13 | 14

By rderooy

Paladin (686)

rderooy's picture

26-04-2017, 23:11

Not sure if this one is well known, but in addition to the Forte Games Arcade board with a ripped version of Knightmare, there is a second one: http://www.pakequis.com.br/2009/05/placa-msx-que-encontrei-d...
Unknown who made it, but it also seems to feature knightmare, but the board is completely different then the one from Forte Games.

By Piter Punk

Master (224)

Piter Punk's picture

27-04-2017, 05:07

rderooy wrote:

Not sure if this one is well known, but in addition to the Forte Games Arcade board with a ripped version of Knightmare, there is a second one: http://www.pakequis.com.br/2009/05/placa-msx-que-encontrei-d...
Unknown who made it, but it also seems to feature knightmare, but the board is completely different then the one from Forte Games.

Very nice! I didn't know about this MSX. It probably had smaller production scale than the one from Forte Games, the board looks handmade. By the pictures this ITS machine have more in common with a normal MSX than with the board of Forte Games (which doesn't have the usual slot handling logic and the BIOS is merged with the Knightmare game).

My guess, looking the dates sticked in the EPROMs, is that someone saw a Forte Games machine, recognized the MSX game and tried to do create a another arcade machine to make some money.

By Piter Punk

Master (224)

Piter Punk's picture

28-03-2019, 02:29

Long time without any news about hidden MSX computers. But even at the underground the quest continues.

This video shows another hidden MSX2 computer booting the Gradiente MSX BIOS. We show this machine at MSX Jaú 2018. We used an MSX1 BIOS instead an MSX2 because the need of an additional slot for SUBROM is troublesome to do the initial tests.

Video showing Gakken GCX Study Computer (audio in portuguese)

Gakken's machine were a bit different than the other hidden MSX's mainly because they have a lot of different models:

  • GCX-1000 - rear proprietary slot, MSX cartridge slot, two joystick ports, integrated cassette
  • GCX-1100 - rear proprietary slot, MSX cartridge slot, one joystick port, card reader, integrated cassette
  • GCX-VN - rear proprietary slot, internal BIOS, one joystick port, card reader, integrated cassette
  • GCX-VCD - rear proprietary slot, proprietary BIOS, one joystick port, card reader, integrated CD-ROM

And even their own line of accessories, like card-readers, PCM modules, CD-ROM controllers, etc.

In the video, I claim that probably the keyboard is accessed in a non-MSX way, that is why we can't type anything after the BIOS boot. I was plain wrong, the real reason is that the Gakken GCX machines uses Z80-CTC to control interrupts, as the MSX's interrupt handler didn't clears the interrupts (using RETI instead of RET) the machine get stuck when interrupts are enabled.

I had hopes to take a lot of pictures, make a blog post, cartridge dumps, etc, before announce this machines. But the spare time is short and I guess that little information is better than no information.

If you have any doubt about this machines and I could help, I'll be very happy to answer.

By Piter Punk

Master (224)

Piter Punk's picture

05-03-2020, 01:19

I guess I found a new hidden MSX.

By sd_snatcher

Prophet (3504)

sd_snatcher's picture

05-03-2020, 01:25

Interesting! Tell us more about it!

By Piter Punk

Master (224)

Piter Punk's picture

05-03-2020, 08:58

It's a very bizarre appliance from Taito, called Taito Presenter 2000.

AFAIK it have two different modes:

  1. A lucky draw mode, with simple games;
  2. A karaoke mode, where it shows patterns on screen.

If you want to see the dumped ROMs, they are available here.

The analogic video board is the same one used by Yamaha in their MSX computers. I still have to do many tests with this equipment, but it's better to have information spreaded than kept in secret. I put some additional pictures and discoveries in this blog post.

It's still not there in the blog, but I found funny what the majority of EPROM contents are: bitmaps! I wrote a small program that substitutes the 0 bits by spaces and the 1 bits by #s. The results were letters, patterns and symbols, like this snippet:

   #   #   #   #   #   #   #   #
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   #   #   #   #   #   #   #   #
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   ## ### ### ##
   ## ### ### ### ### ##   #   #
   ## ### ##   ## ### ### ##   #
   ## ### ##   #   ## ### ### ##
   #   #   #   #   #   #   #   #
   ## ### ### ### ### ### ### ##
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   ## ### ### ### ### ### ### ##
   #   #   #   #   #   #   #   #
   #   ## ### ### ### ##   #   #
   ## ### ##   #   ## ### ##   #
   ## ### ##   #   #   #   #   #
   #   ## ### ### ### ### ##   #
   #   #   #   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   #   ## ### ### ### ### ##   #
   #   #   #   #   #   #   #   #
   ## ### ### ### ### ### ### ##
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   ## ### ### ### ### ### ### ##
   #   #   #   #   #   #   #   #
   ## ### ##   #   #   ## ### ##
   ## ### ### ##   #   ## ### ##
   ## ### ### ### ##   ## ### ##
   ## ### ### ### ### ### ### ##
   ## ### ##   ## ### ### ### ##
   ## ### ##   #   ## ### ### ##
   ## ### ##   #   #   ## ### ##
   #   #   #   #   #   #   #   #
   #   ## ### ### ### ### ### ##
   #   #   #   ## ### ##   #   #
   #   #   #   ## ### ##   #   #
   #   #   #   ## ### ##   #   #
   #   #   #   ## ### ##   #   #
   #   #   #   ## ### ##   #   #
   #   #   #   ## ### ##   #   #
   #   #   #   #   #   #   #   #
   ## ### ### ### ### ### ### ##
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   #   #   #
   ## ### ##   #   #   #   #   #
   ## ### ### ### ### ### ### ##
   #   #   #   #   #   #   #   #
   ## ### ### ### ### ### ##   #
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   ## ### ### ##
   ## ### ### ### ### ##   #   #
   ## ### ##   ## ### ### ##   #
   ## ### ##   #   ## ### ### ##
   #   #   #   #   #   #   #   #
   #   #   #   #   #   #   #   #
   #   #   #   #   #   #   #   #
   #   #   #   #   #   #   #   #
   #   ## ### ### ### ##   #   #
   #   ## ### ### ### ##   #   #
   #   #   #   #   #   #   #   #
   #   #   #   #   #   #   #   #
   #   #   #   #   #   #   #   #
   #   ## ### ### ### ### ##   #
   ## ### ##   #   #   ## ### ##
   #   #   #   #   ## ### ### ##
   #   #   ## ### ### ### ##   #
   #   ## ### ### ### ##   #   #
   ## ### ### ##   #   #   #   #
   ## ### ### ### ### ### ### ##
   #   #   #   #   #   #   #   #
   #   #   ## ### ### ##   #   #
   #   ## ##   #   ## ### ##   #
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   #   ## ### ##   #   ## ##   #
   #   #   ## ### ### ##   #   #
   #   #   #   #   #   #   #   #
   #   #   ## ### ### ##   #   #
   #   ## ##   #   ## ### ##   #
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   #   ## ### ##   #   ## ##   #
   #   #   ## ### ### ##   #   #
   #   #   #   #   #   #   #   #
   #   #   ## ### ### ##   #   #
   #   ## ##   #   ## ### ##   #
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   ## ### ##   #   #   ## ### ##
   #   ## ### ##   #   ## ##   #
   #   #   ## ### ### ##   #   #
   #   #   #   #   #   #   #   #

There are 48KB of this stuff.

By hamlet

Scribe (4097)

hamlet's picture

05-03-2020, 09:41

I enjoy reading your report about hidden MSX hardware and find it very fascinating. Thank you for the effort!

By tfh

Prophet (3160)

tfh's picture

05-03-2020, 09:59

Indeed... Looking forward to future reports. I love reading about your quests.

By sdsnatcher73

Prophet (3032)

sdsnatcher73's picture

05-03-2020, 18:36

It seems (to me) Taito in this case just contracted Yamaha to build a device for Taito to put software on. Yamaha went with the components they made and had knowledge of from their MSX endeavors.

By Piter Punk

Master (224)

Piter Punk's picture

05-03-2020, 19:11

sdsnatcher73 wrote:

It seems (to me) Taito in this case just contracted Yamaha to build a device for Taito to put software on. Yamaha went with the components they made and had knowledge of from their MSX endeavors.

Yes, people at MSXSP meeting thought in this possibility. Mainly after I said the internal devices were all accessed by memory regions, without any "out" or "in" the ROM code.

I still think that we must first try with an MSX BIOS ROM and take a better look in the board and those dip switches. Maybe it can work as a keyboard-less MSX.

Maybe there was an idea to have a optional board with keyboard connected in the expansion connector? The connector goes to the PPI lines. It seems feasable and, to me, is more in line with an "PC BOARD" as it's silked in the main board.

Page 12/14
5 | 6 | 7 | 8 | 9 | 10 | 11 | | 13 | 14