Atari ST series Technical Reference Manual page 47

XBIOS Device and System Functions
Table 3-4. Data Block Pointed to by params
Byte
Offset Label
0
topmode
1 buttons
2 xparam
3 yparam
4* xmax
6*
ymax
8*
xinitial
10*
yinitial
Used only in mouse absolute mode.
The vector variable is used to pass the address of new
mouse packet interrupt handler. If you're changing the mouse
mode, chances are that the current handler will not work.
Both the MIDI and IKBD devices can send input to the
ST, as well as receive output. Receiving input is a little more
complex than sending output, however. Input from these de­
vices is handled by a number of system interrupt routines
which store the characters received in buffers. Information
on the input buffers is provided in the section on the Iorec()
function, above. The XBIOS also provides a function called
Kbdvbase(), which returns pointers to several of the actual
interrupt routines that are used to handle the input func­
tions. The syntax for this function is:
long vecbase;
vecbase = Kbdvbase();
where vecbase contains the address of a vector table. The
structure of this vector table is as follows:
Table 3-5. Vector Table Structure Pointed to by vecbase
Byte Vector
Offset Name
0 midivec
4 vkbderr
8 vmiderr
Specifies origin of
0 = y origin (0 point) at bottom
1 = y
origin at top
The parameter for the IKBD set mouse buttons
command
In relative mode,
In absolute mode,
In keycode mode,
In relative mode,
In absolute mode,
In keycode mode,
x
Maximum position of mouse
y
Maximum position of mouse
x
Initial position of mouse
y
Initial position of mouse
Routine Called
MIDI input routine
IKBD ACIA overrun error routine
MIDI ACIA overrun error routine
Description
y
position
x
threshold
x
scale
x
delta
y
threshold
y
scale
y
delta
{ '
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