Software Interrupt Map - Tandy 600 Programmer's Reference Manual

Software
Interrupt
Map
The BIOS
software
interrupt
assignments
are
shown
below. During cold
start initialization,
the
BIOS
must
initialize
the interrupt
vectors
to
point
to
the appropriate support routine within the
BIOS.
Interrupt
Function
Number
40h-4Ah Reserved,
initialized
to point to
a
dummy
I
RET
in
the
BIOS
48h
Touch
Panel
Hook (IRET)
—
Unsupported Software
Interrupt
4Ah Ring Detect Hook,
initialized
to point to
a
dummy
IRET
in
the
BIOS
4Bh Touch Panel Hook,
initialized
to point
to
a
dummy
IRET
in
the
BIOS
4Ch
RS-232
Receiver
Queue
Hook,
initialized
to point to
a
dummy
IRET
in
the
BIOS
4Dh
Interval
Timer Hook,
initialized to
point
to
a
dummy
IRET
in
the
BIOS
4Eh Power
Low/Off Hook,
initialized to
point
to
a
dummy
IRET
in
the
BIOS
4Fh Keyboard
Queue
Hook,
initialized to
point to
a
dummy
IRET
in
the
BIOS
50h
Keyboard Support
51 h
LCD
Text
Support
52h
LCD
Graphics Support
53h
Cassette Support
—
Unsupported Software
Interrupt
54h
Calendar/Clock/Alarm Support
55h
Sound
Support
56h
Printer
Support
57h Disk Support
58h
Power
Off
59h
Communications/Modem
Support
5Ah Bar
Code
Reader Support
—
Unsupported Software
Interrupt
5Bh Touch Pannel Support
—
Unsupported Software
Interrupt
5Ch-6Fh Reserved,
initialized to
point to
a
dummy IRET
in
the
BIOS
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