Basic Disk Operating System (BDOS) Functions
4-4
Simple
BDOS
Calls
BDOS functions 0 through
12
perform such simple operations as system reset
and
single character
1/0.
SYSTEM
RESET
ENTRY
CL:
OOH
DL:
Abort
Code
RETURN
FUNCTION
0
SYSTEM RESET
The System Reset function returns
control
to
the
CP
1M
operating system
at
the
CCP
command
level. The
abort
code passed in
DL
has two possible values.
IfDL
is
OOH,
the currently active
program
is
terminated
and
control
is
returned
to
the CCP.
If
DL
is
01H,
the
program
remains in
memory
and
the memory allocation is
unchanged.
CONSOLE
INPUT
ENTRY
RETURN
CL:
OlH
FUNCTION
1
AL: ASCII Character
CONSOLE
INPUT
The Console
Input
function reads the next character from the logical console device
(CONSOLE) into register AL.
Graphic
characters
and
the carriage return, line feed,
and
backspace
(CONTROL-H)
are echoed
to
the console.
Tab
characters
(CONTROL-I)
are expanded in columns
of
eight characters.
The
BDOS does
not
return
to
the calling
program
until a character has been typed, thus suspending
execution
if
a character
is
not ready.
NOTE
The
status
of
the
GRAPH1, GRAPH2,
CAPS
and
AL
T keys is
not
returned
by
the BDOS
call.
To
access these values,
you
must call the
CBIOS directly.
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