+-------------+
				|    Vic 20   |
				+-------------+

		  Vic-20 ROMs (C) Commodore Business Machines


MACHINE SETUP MENU
------------------

The VIC 20 specific setup menu accessed from iYASE menu is described here.
The options are :

Setup			- Display the setting for the VIC.  These are described
			  further on.
Remove cartridge	- Remove cartridge.
Done			- Return to iYASE main menu


The setup dialog has these options (* = Only applied on next reset) :

Ram size (*)		- Pick from either an unexpanded VIC 20, or a VIC with
			  either a 3K, 8K, 16K or 24K RAM pack.

Disk drive (*)		- Attach the VIC disk drive.  This option is not
			  yet done.

Frame skip		- Skip N frames between each redraw.

Stop on BRK		- Generates a break point to the iYASE memory menu
			  whenever a BRK opcode is evaluated.

Use mouse for		- If a mouse is available, the mouse can be used for
			  either paddle or the light pen.  This option is
			  not yet done.

Auto insert cart	- There are 2 cartridge sizes handled by iYASE.
			  A 4K cartridge is always loaded at 0xb000.  If
			  the cartridge is 8K big and the auto insert option
			  is on then the cartridge is placed at 0xa000 (the
			  proper place for self-running carts).  If the option
			  is off then you will be asked to insert the cartridge
			  at either 0x2000, 0x6000 or 0xa000.

Read keys on interrupt	- The keyboard is either read on a screen update
			  (the default - slightly less repsonsive, but should
			  always work) or on the generation of an interrupt
			  (which is perfect in the response states, but
			  useless if no interrupts happen).


KEYBOARD
--------

The key layout is as expected for standard keys.  On a technical note the
keyboard is read during the redraw of the screen, rather than on generation of
an interrupt be defualt.  As an interrupt generally happens before the screen
is redrawn this is settable (though once set to interrupts if no VIA interrupts
are occuring the keys may stop responding entirely).

The Vic 20 had quite a rich keyboard for an old 8-bit micro (though bizarrely
doesn't have all 4 cursor keys?!?), so punctuation and special keys are mapped
as follows (note the iYASE punctuation keys refer to a UK layout) :

Vic 20 key		iYASE key

F1			F1
F3			F2
F5			F3
F7			F4

<-			` (Top left)

Commodore		Left alt
Shift lock		Left shift
Run stop		Tab
-			-
+			=
Pound sign		End
Home key		Home
Delete			Backspace

@			[
*			]
^ Pi			Insert
Restore			Right alt or Right Control

: [			;
; ]			'
=			#

, <			,
. >			.
/ /			/

Cursor down		Cursor Down
Cursor right		Cursor Right
Cursor up		Shift + Cursor Down
Cursor left		Shift + Cursor Right


JOYSTICK
--------

The joystick is emulated.  Paddle and light pen support to be added.


OUTSTANDING/BUGS
----------------

Still to do	: Loading/saving to tape
		  Proper handling of different cart types


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$Id: vic20.txt,v 1.1 1999/09/27 12:08:14 dosuser Exp dosuser $