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***************      WELKOM TO AVR.FORTH FOR DOS65             ***************
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    This public domain publication is provided through the courtesy of
    HCC-FORTH INTRESSE GROEP, c/o Medemblikpad 70, 8304 cz EMMELOORD,
    Netherlands.

This disc contains several FORTH files.
One of these files is AVR.FORTH which is the base of this forth.
The other files are     EXTEN.FTH
			EDITOR.FTH
			ASSEM.FTH
			WFORTH

Al of these files except WFORTH are compiled an stored under the name FORTH.
If you want to make changes in the editor or assembler you can build a new 
forth using AVR.FORTH and the input redirect.

For instance :
		< EXTEN.FTH AVR.FORTH
		save 0:FORTH 2000,xxxx
		< EDITOR.FTH FORTH
		save 0:FORTH 2000,xxxx
		< ASSEM.FTH  FORTH
		save 0:FORTH 2000,xxxx

If you are working in forth an want to go back to dos use MON.
You can reenter forth with WFORTH.
Words added to the model:

DEC.		print 16 bit number on top of the stack as a signed 
		decimal number not changing the base.
HEX.		print 16 bit number on top of the stack as a unsigned 
		hexadecimal number not changing the base.
@SEC1		This word reads track 0 sector 1 of the disc, with
                the information on this sector the variables :
		ddsd		dubble or single density
		maxscr		number of forth screens
		sectr		number of sectors on one disc
		sectl		number of sectors of two disc's
		are set correctly with the word INITDRIVE.

When the word ABORT is executed, INITDRIVE is executed, en track zero,
sector one of the users drive is copied to $1000 as lookup table for
the dos routine read and write sector, also the above mentioned variables
are set.

If there is only one drive available then you have to LOAD FORTH en
then load the monitor.
Change the value's in memory location $3613 en $3695 from 01 to 00.
If you startup FORTH sector one of track zero of drive zero is copied 
to $1000 as lookup table.
If the system disc is not formatted in the same way as your 
FORTH disc then you have to execute the word INITDRIVE

Instead of the word "OK" the prompt will be the base followed by a >
like 16> or 10> or 2> .

CHKSCR is a variable which hold the max nr of screens you can handle
with one or two drive's.
LIST an LOAD verifies the screen number by calling chkscr before
loading or listing.

AVR.FORTH is extended with some handy words.
This file is also on this disc so if you want to make changes go ahead.
The file name is " EXTEN.FTH " .

JSR		jump to a subroutine in dos 65  ( xxxx jsr )
.S		print contains of stack
DUMP		hex an ascii dump  ( adress  nr  dump )
REVID		reverse video
VID		back to normal video
CLS		clear screen
BEL		sounds bel if avialable
BIN 		set base to binaire
COPY		copy screen on the same disc  ( 10 20 copy )
0:		select disc 0 
1:		select disc 1 
DATE		set date on the status line.
TIME    	set time on status line.
PRT-ON		printer on ( doesn't look if printer is there )
PRT-OFF		printer off
BACKUP		copies screens from disc 1 to disc 0 ( remove system disc )
                10 20 backup copies screen 10 thru 20 from disc 1: to 0:


The editor used with this forth is the screen editor which was published
in the 6502 kenner nr 42 by Fridus jonkman.
The file name " EDITOR.FTH "

Commands used on this editor are :
^A	curser to the left.
^D	curser to the right.
^E	curser up.
^F	delete character.
^H	curser home.
^I	delete one line al lines go one up.
^J	erase till the end of the line.
^K	get line where curser is into buffer.
^L	clear screen curser home.
^M	curser to next line (cr)
^N	put the buffer on line where curser is.
^O	insert new line all lines one down.
^T	save screen on disc.
^U	leave editor go back to forth.
^X	curser down.
^V	insert or overstrike mode.

For more information check 6502 kenner nr 42.

The assembler used is the assembler for the 65c02 which was published
in the 6502 kenner nr 46 by Gert klein.
File name " ASSEM.FTH "
This assembler is not fully tested on this forth ,so take care.
                                                      T.W borst