User`s manual

GEOS and BASIC
If you are a BASIC programmer, you can enter and use the BASIC environ-
ment directly from the GEOS
deskTop.
To enter BASIC from the deskTop:
Select BASIC from the special menu. You will enter the Commodore
BASIC interpreter.
Using the BASIC Interpreter from the deskTop
Once you have entered the Commodore BASIC interpreter, your Commo-
dore will
run much as before except that the default NMI vector will be
replaced with a vector to some
reboot code for the deskTop in the $C000
memory space. This will allow the deskTop to be rebooted by inserting the
originid GEOS boot disk into the disk drive and pressing the -1
key on the keyboard.
Running BASIC Programs from the deskTop
Any BASIC program can be loaded and run from the deskTop. If the
program is smaller than
26K, the GEOS diskTurbo software will fast-load
the program into memory and automatically execute a
RUN command. If
the program is larger than 26K. it will be loaded by the normal Commodore
DOS routines and a
RUN command will be executed.
To run a BASIC program from the deskTop:
Double-click on the program's file icon on the disk note pad page.
Returning to the deskTop
If the programs you have run while in the BASIC interpreter do not disturb
the memory space between
$C000 and $C080 (hex address values), and the
NMI vector has not been changed, then you can reboot the deskTop.
To reboot from BASIC:
1: Place the original GEOS boot disk into Drive A.
2: Press the -1 key.
To reboot from BASIC without losing the contents of an REU:
Type LOAD"RBOOT",8,1.
The deskTop 41