Motorola CPU32 Reference Manual page 48

LOW MEMORY
(FREE)
PUT – (An)
LAST PUT
NEXT GET
GET – (Am)
LAST GET (FREE)
HIGH MEMORY
To implement the queue as a circular buffer, the "get" or "put" operation should be per-
formed first, and then the relevant address register should be checked and (if neces-
sary) adjusted. The address register is adjusted by adding the buffer length (in bytes)
to the register contents.
MOTOROLA DATA ORGANIZATION AND ADDRESSING CAPABILITIES CPU32
3-18 REFERENCE MANUAL