Echelon Neuron - Manual (Page 77)

ALLOC (Allocate)
The ALLOC instruction allocates a specified number of bytes on the data stack.
The specified number of bytes must be in the range 1 to 8. The ALLOC
instruction uses the immediate addressing mode. The allocated bytes are not
initialized and have non-deterministic values.
Recommendation: Use the _alloc system function to allocate more than eight
bytes on the data stack, or to allocate any number of bytes that will be initialized
to zero. See _alloc (Allocate Stack Space) for more information.
See also DEALLOC (Deallocate and Return) to deallocate space on the data stack.
The ALLOC instruction applies to Series 3100, 5000, and 6000 devices.
Syntax:
The ALLOC instruction requires a single operand to specify the number of bytes
to allocate on the data stack:
ALLOC #number
The value of number must be in the range 1..8. The number sign or hash (#) is
required to specify the immediate value.
Table 13 describes the attributes of the ALLOC instruction.
Table 13. ALLOC Instruction
Instruction Hexadecimal
Opcode
Instruction
Size (Bytes)
CPU Cycles
Required
Affect on
Carry Flag
ALLOC #1 C0 1 3 None
ALLOC #2 C1 1 3 None
ALLOC #3 C2 1 3 None
ALLOC #4 C3 1 3 None
ALLOC #5 C4 1 3 None
ALLOC #6 C5 1 3 None
ALLOC #7 C6 1 3 None
ALLOC #8 C7 1 3 None
Example:
The following example allocates two bytes on the data stack. The resulting
values of TOS and NEXT are not specified.
alloc #2 ; (a, b)
Neuron Assembly Language Reference 67