Contents |
Description
Computer
The Hitachi MB-H21 looks like a MB-H2 without its data recorder. It has a CPU speed controller switch, allowing slow games execution. The Cassette Operation Guide is replaced by a game: Roulette.
This model was aimed at the Japanese market. It has been localized for the Arabic countries - see Sakhr AH-200.
It was also planned to put the MB-H21 firmware in a model similar to the MB-H1, localized for Europe, but it has never been released - see MB-H80
| Brand | Hitachi |
| Model | MB-H21 |
| Year | 1984 |
| Region | Japan |
| Launch price | ¥49,800 |
| RAM | 32kB (? in slot 0) |
| VRAM | 16kB |
| Media | MSX cartridges |
| Video | Texas Instruments TMS9118NL |
| Audio | PSG (AY-3-8910) |
| Chipset | none (separate IC's) |
| Keyboard layout | QWERTY/JP50on |
| Extras | CPU speed controller switch, firmware (Sketch Program, Sound Play, Roulette, MB-H21 Monitor Program) |
| Emulation | ROM dump needed. See this thread for details |
Firmware
The firmware available in this computer uses function keys F1 to F5:
- F1 - MSX-BASIC (F1)
- F2 - Sketch Program (graphic program)
- F3 - Sound Play (music keyboard)
- F4 - Roulette (game) and the
- F5 - MB-H21 Monitor Program (disassembly/monitor of machine code)
There is no any key to bypass the firmware menu when booting because it is auto-bypassed when a ROM cartridge is inserted.
If you stay on the menu, an automatic demo of the Sketch-Sound options will begin after a few time.
When you have started an application, you can go back to the menu by entering E in the monitor or by pressing CTRL+STOP in the other applications.
From MSX-BASIC, you can
- access to the command line of the Monitor with CALL MON or _MON (to get the list of all available commands in this utility, enter H on the command line - back to BASIC by entering E)
- send a screendump of a text screen to a connected printer with CALL HCOPY or _HCOPY.
Pictures
Computer
Firmware
Will be added later - the pictures should be similar to the Hitachi MB-H2 firmware, except for the Cassette Operation Guide, replaced by Roulette.
Specifications
The MB-H21 is a MSX1 with a CPU speed controller for slow games execution. The CPU is a Z80A from Sharp (LH0080A).
The firmware is auto-bypassed when a cartridge is inserted in the slot 1 or 2 but it not working with a slot expander. To remedy this drawback, you have to insert a ROM cartridge in one of the two primary slots.
Slot Map
| Slot 0 | Slot 1 | Slot 2 | Slot 3 | ||||
|---|---|---|---|---|---|---|---|
| Page C000h~FFFFh | Cartridge Slot 1 | Cartridge Slot 2 | 32kB RAM | ||||
| Page 8000h~BFFFh | Firmware | ||||||
| Page 4000h~7FFFh | Main-ROM | ||||||
| Page 0000h~3FFFh |
Connections
- RF output
- Analog sound & Composite video
- Data Recorder connector
- Centronics compatible Parallel port for a printer
- 2 general connectors (Joysticks, Mouse, Paddle controllers, etc)
- 2 cartridge slots