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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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