WonderWitch

The WonderWitch is an official homebrew development kit released by Qute Corporation on July 18th, 2000.

Hardware

The WonderWitch cartridge is based on the Bandai 2003 mapper. It provides an RTC, as well as NOR self-flashing functionality using the Fujitsu MBM29DL400TC chip.

There were three means of acquiring WonderWitch cartridges:

• WonderWitch, a software development kit containing a reflashable cartridge, a WonderSwan<->RS-232 adapter, a development manual and a development tool CD;
• WonderWitch Player, a priced-down user-only version omitting the development manual and tooling;
• The VAR program, allowing independent creators to buy reflashable cartridges in bulk, in units of 20 or 100.

Software

The WonderWitch provides an abstraction layer and helper libraries, split into two modules:

• FreyaBIOS - providing a hardware abstraction layer and some utility functions,
• FreyaOS - providing helper libraries and higher-level concepts, such as processes and files.

Memory map

Internal RAM (0x00000 - 0x0FFFF)

From	To	Description
0x00000	0x00???	Interrupt vectors
0x00???	0x00???	???
0x00E00	0x03FFF	Space used by user programs (sprite, screen, tile data)
0x04000	0x0BFFF	Space used by user programs (color tile data)
0x0C000	0x0FDFF	???
0x0FE00	0x0FFFF	Space used by user programs (color palette data)

Cartridge flash (0x80000 - 0xFFFFF)

The 512KB of NOR flash memory is mapped and partitioned as follows:

Linear address	Size	Description
0x8nnnn	384 KB	File system
0x9nnnn
0xAnnnn
0xBnnnn
0xCnnnn
0xDnnnn
0xEnnnn	64 KB	FreyaOS
0xFnnnn	64 KB	FreyaBIOS

Interrupt vectors

Start	End	Description
0x00	0x07	CPU interrupts
0x08	0x0F
0x10	0x18	FreyaBIOS interrupts

Internal console RAM is generally managed by FreyaBIOS, while SRAM is managed by FreyaOS.

Development tools

TODO

Links

• Fujitsu MBM29DL400TC datasheet