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Basic Disk Operating System (BDOS) Functions
4-10
GET CONSOLE STATUS
ENTRY
RETURN
CL: OBH
FUNCTION 11
AL: Console Status
GET CONSOLE STATUS
The Get Console Status function checks to see if a character has been typed at the
logical console device (CONSOLE). If a character is ready, the value 01H is
returned in register AL. Otherwise the value OOH is returned.
RETURN VERSION NUMBER
ENTRY
RETURN
CL: OCH
FUNCTION 12
BX: Version Number
RETURN VERSION NUMBER
The Return Version Number function provides information which allows version-
independent programming. A two-byte value is returned designating the CP/M
version number, as follows.
BDOS File Operations
BH
00
00
00
00
01
BL
00
20
2l-2F
22
Version
CP/M
<
2.0
CP/M 2.0
CP/M> 2.0
CP/M-86
MP/M
Functions 13 through 52 are related to disk file operations under CP/M-86. In
many of these operations, DX provides the DS-relative offset to a File Control
Block (FCB). The FCB data area consists of a sequence of 33 bytes for sequential
access, or 36 bytes for random access. The default FCB normally located at offset
005CH from register DS can be used for random access files, since bytes 007DH,
007EH, and 007FH are available for this purpose.
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