System information

Following the ENDEF macro call, a number of uninitialized data areas are defined. These data
areas need not be a part of the BIOS that is loaded upon cold start, but must be available between
the BIOS and the end of memory. The size of the uninitialized RAM area is determined by EQU
statements generated by the ENDEF macro. For a standard four-drive system, the ENDEF macro
might produce the following EQU statement:
4C72 = BEGDAT EQU $ (data areas)
4DBO = ENDDAT EQU $
013C = DATSIZ EQU $-BEGDAT
which indicates that uninitialized RAM begins at location 4C72H, ends at 4DB0H-1, and
occupies 013CH bytes. You must ensure that these addresses are free for use after the system is
loaded.
After modification, you can use the STAT program to check drive characteristics, because STAT
uses the disk parameter block to decode the drive information. A STAT command of the form:
STAT D:DSK:
decodes the disk parameter block for drive d (d = A,...,P) and displays the following values:
r: 128-byte record capacity
k: kilobyte drive capacity
d: 32-byte directory entries
c: checked directory entries
e: records/extent
b: records/block
s: sectors/track
t: reserved tracks
6.11 The DISKDEF Macro Library CP/M Operating System Manual
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