Motorola CPU32 Reference Manual page 160

MOVEP Move Peripheral Data
Operation:
Assembler
Syntax:
Attributes:
Source => Destination
MOVEP Ox, (d, Ay)
MOVEP (d, Ay), Ox
Size
=
(Word, Long)
MOVEP
Description: Moves data between a data register and alternate bytes within the address space
(typically assigned to a peripheral), starting at the location specified and incrementing by two. This
instruction is designed for 8-bit peripherals on a 16-bit data bus. The high-order byte of the data
register is transferred first and the low-order byte is transferred last. The memory address is
specified by the address register indirect plus 16-bit displacement addressing mode. If the
address is even, all the transfers are to or from the high-order half of the data bus; if the address is
odd, all the transfers are to or from the low-order half of the data bus. The instruction also
accesses alternate bytes on an 8- or 32-bit bus.
Example: Long transfer to/from an even address.
Byte Organization in Register
31
24 23 16 15
8
HIGH ORDER MID-UPPER MID-LOWER
Byte Organization in Memory (Low Address at Top)
15 8 7
o
HIGH ORDER
MID-UPPER
MID-LOWER
LOW ORDER
CPU32 REFERENCE MANUAL INSTRUCTION SET
7
o
LOW ORDER
MOTOROLA
4-107
III