BLOCK error. If there are no blocks available that are greater in number than
the one requested, zeroes are displayed as track and sector parameters.
The format “B-A”dr;t;s is illustrated in the following example.
Example:
“B-A”0;10;0
Requests that block (sector)0 of track 10 be flagged as allocated on the
diskette.
NOTE
The error channel should always be checked when
using block allocate, so that if the block is already
allocated, it will not be overwritten. If the block is
allocated, the error message will also indicate the
next available block.
Example:
INPUT#15,EN,EM$,ET,ES
Reads the next track and sector, respectively, into ET and ES, assuming
that lfn=15 has been previously OPENed to the disk error channel.
MEMORY
All three MEMORY commands are byte oriented so that the user can utilize
machine language programs. BASIC statements may be used to access informa-
tion through the MEMORY commands by using the CHR$ function. The sys-
tem accepts only M-R, M-W, and M-E. Neither verbose spelling nor the use of
the colon (:) is permitted.
Memory-Write
This command provides direct access to the DOS memory. Special routines may
be uploaded to the disk drive through this command and then executed using
the MEMORY-EXECUTE command or one of the USER (U) commands. Up
to 34 bytes may be deposited with each use of the command. The low byte of the
address must precede the high byte of the address.
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