| Content of these pages are owned and copyrighted by the poster. | |
| Hosted by: |
|
jos.platform.keyboard virtualizes the keyboard into a series of KeyEvents: PRESSED, RELEASED, and TYPED. jos.system.console (should it be in platform?) abstracts an output console with methods strongly similar to (n)curses -- getCharAt(x,y), setChar(x,y), etc. The console architecture is a bit simpler than the keyboard's, so I'll cover it first. A daemon, consoled, blocks on events from keyboard. When it recieves an event, it dispatches it to the current console, unless the event signals a switch of consoles. consoled uses Focus events to pass along these signals to the consoles. The consoles use ConsoleDrivers to write to the screen. The two ConsoleDrivers should be the host build's ncurses-based driver, and the i386 build's write-to-VGA-port driver. A primitive VGA driver is available for the i386 build as well.
jos.platform.keyboard serves as a router of keyboard events, and the `well-known class' to which listeners interested in scancode or key events subscribe. Keyboard events are generated by a InterruptListener (jos.platform.driver.keyboard) which reads scancodes from the hardware and enqueues them for later dispatch. keyboardd dispatches the scancode events to j.p.keyboard, which re-dispatches them to interested listeners and the KeyboardInterpreter which converts scancodes to key events, and dispatches them back to j.p.keyboard. Finally, the `well-known class' j.p.keyboard dispatches the key events to its listeners (the rest of the system). On the host build, the keyboard is, IIRC, emulated as h/w, though the host build could easily use a driver.keyboard which used native code to query (n)curses.
-- ToddMiller ( 22 June 2001 )
| Content of these pages are owned and copyrighted by the poster. | |
| Hosted by: |
|