Atari ST series Technical Reference Manual page 327

The line A
space, in which much of the system's graphics data is stored.
The location of this variable table may vary from machine to
machine, and from one version of TOS to another, but it can
always be found by calling the Line A Initialization function
(see Chapter 7 for more details). When this function is called,
the base address of the line A variable table is returned both
in register AO and DO. Starting at this base address, you can
locate the variables in the table by using their offset from the
base address. The following chart shows the offset of each
line A variable in decimal and hexadecimal format, its name,
and a description of its contents. Those variables whose
names start with V__are used by the ST BIOS character out­
put routines.
-9 1 0 to -9 0 5
This area is reserved for internal use.
-9 0 6 to -9 0 1
A pointer to the current font header is stored here.
-9 0 2 to -8 5 5
This area is reserved for internal use.
The Following 37 Words Hold the Sprite Definition
Block for the Mouse Pointer
-8 5 6 to -8 5 5
routines use about IK of variable
RESERVED
CUR__FONT
RESERVED
M__POS__HX
( — $38E to -$389)
(-$ 3 8 8 to -$387)
(-$ 3 8 6 to -$355)
(-$ 3 5 6 to -$355)
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