User guide

or in assembly language—a simple example which plots points relative to the Mouse
position:
10 .forever LDA # 64
20 LDX # block MOD 256
30 LDY # block DIV 256
40 JSR osword
50 / PL0T 69,xcord,ycord
60 LDA # 25
70 JSR oswrch
80 LDA # 69
90 JSR oswrch
100 LDX # 0
110 .loop LDA block,X
120 JSR oswrch
130 INX
140 CPX # 4
150 BNE loop
160 JMP forever
e.g. *BR.
The function of this command is to simulate the pressing of the BREAK key. It must
be used whenever a *POINTER ON or *POINTER OFF command are used. This is in order
to reserve workspace for storing the pointer icon and mask by altering the value of the
PAGE:
If a second processor is used, the workspace is ALWAYS reserved. Therefore when
the *BREAK command is used it will have no effect except for executing any *KEY 10
routines.
Whenever *BREAK is used the break key (*KEY 10 ) should be programmed to
chain your program. For example the !BOOT file on the disc is:
*KEY 10 CHAIN "!MENU"|M
*P0INTER 0N
*BREAK