WonderWitch applications compiled using the official Qute SDK require a copy of FreyaOS (and FreyaBIOS) to run. Unfortunately, nowadays a loose WonderWitch cartridge required to run such programs can go for as much as $100 on the second-hand market, with the full SDK fetching prices above $200 - much more than the console itself. This makes not just creating, but even running WonderWitch applications inaccessible to most hobbyists.

(If you're an employee of Qute Corporation reading this, I would be very happy to volunteer and help resolving this situation.)

However, there already exists a large base of tutorials and software, including open source software, written for the API provided by Freya. One way to facilitate interoperability between the Wonderful toolchain (and, by extension, alternate execution environments) and such WonderSwan software would be to reimplement the required parts of the Freya API. In the past, projects like WSSim and WWWLib have been created to achieve this, as well as dedicated emulators like MiracleMage.

The Wonderful toolchain provides the libwwcl (WWitch Compatibility Layer) library for this purpose - a clean room reimplementation of selected Freya APIs.

To create a libwwcl project template, use the -t wwcl argument when creating a new project:

  $ wf-wswantool project new -t wwcl new_project_name

• While a Freya application uses the Makefile to configure the default memory layout (ASCII1, ASCII2, JAPANESE1, JAPANESE2), libwwcl relies on WWCL_INIT_MODE macros and the wwcl_init() function for this.
  • These macros and functions are provided in <wwcl.h>, which is a new header that can be used instead of <sys/bios.h>.
  • The macros are entirely optional. If you want to declare the memory layout yourself using the Wonderful toolchain's memory management, that is supported - use wwcl_init_custom() in this situation.
• gcc-ia16 requires a __far modifier for all constant arrays stores in ROM. See Addressing RAM and ROM for more information.
• The Text API operates on Shift-JIS strings. To make gcc-ia16 use Shift-JIS strings instead of UTF-8 strings, pass -fexec-charset=shift-jis.

The implementation is incomplete; you can help by expanding it.

• The following headers should be fully implemented:
  • Display (disp.h)
  • Color (libwwc.h)
  • Sound (sound.h)
• Bank (bank.h) is not implemented.
• Comm (comm.h) implements everything except comm_xmodem.
• Key (key.h) is missing key repeat support.
• Text (text.h) is not implemented.
• Timer (timer.h) is missing RTC (real time clock) support.
• The implementation of System (system.h) is very limited. However, many of its functions are not useful when not running on top of Freya.