Allocate - ZiLOG Z80-RIO Operating System User's Manual

5.2
ALLOCATE
ALLOCATE
(Internal Command)
SYNTAX
Allocate low_boundary high_boundary block size
DESCRIPTION
Attempts to allocate block size bytes (rounded
up to a multiple of 80H bytes) of memory. The search
begins at address low boundary (rounded down modulo 80H),
and the first block large enough and not extending beyond
high boundary (rounded up to the next multiple of 80H - 1)
is marked as allocated in the system memory map. If allocation
is not possible, the message INSUFFICIENT MEMORY is given.
I/O UNIT UTILIZATION
None
EXAMPLES
ALLOCATE 0 FFFF 120
starting at memory address 0, a search is made for
a 180H byte (120H bytes rounded up to a multiple of
80H) memory segment.
ALLOCATE 5300 537F 80
attempts to allocate the single 80 byte memory segment
starting at 05300H.
ALLOCATE 7400 8000 400
INSUFFICIENT MEMORY
no 400H byte block is available in the address range
7400-807FH.
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