5. Loadable drivers

Note: Since the Apple ][ doesn't have working disk I/O (see section "Limitations"), the available drivers cannot be loaded at runtime (so the term "loadable drivers" is somewhat misleading). Instead, the drivers have to be converted using the co65 utility and statically linked. While this may seem overhead, it has two advantages:

1. The interface is identical to the one used for other platforms and to the one for the Apple ][ once it has disk I/O.
2. Once disk I/O is available, existing code can be changed to load drivers at runtime with almost no effort.

5.1 Graphics drivers

Note: Since memory for the high resolution graphics has to be allocated, programs using graphics drivers will have to be linked using a special linker configuration. See the apple2-tgi.cfg file in the documentation directory, and the linker documentation on how to use it.

a2.lo.tgi

This driver was written by Stefan Haubenthal. It features a resolution of 40×40 with 16 colors. At the bottom of the screen, 4 additional text lines are available.

a2.hi.tgi

This driver was written by Stefan Haubenthal. It features a resolution of 280×192 with 6 colors.

5.2 Extended memory drivers

a2.lc.emd

Gives access to 12KB RAM (48 pages of 256 bytes each) on the Apple ][ language card. The driver was contributed by Stefan Haubenthal. Note: This driver is incompatible with any DOS using the language card memory!

5.3 Joystick drivers

a2.stdjoy.joy

Supports up to two standard analog joysticks connected to the game port of the Apple ][.

5.4 Mouse drivers

Currently no drivers available (in fact, the API for loadable mouse drivers does not exist).

5.5 RS232 device drivers

No serial drivers are currently available for the Apple ][.