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MOVEM
Operation:
Assembler
Syntax:
Attributes:
Description:
memory locations starting at the location specified by the effective address. A register
is selected if the bit in the mask field corresponding to that register is set. The instruc-
tion size determines whether 16 or 32 bits of each register are transferred. In the case
of a word transfer to either address or data registers, each word is sign-extended to
32 bits, and the resulting long word is loaded into the associated register.
Selecting the addressing mode also selects the mode of operation of the MOVEM
instruction, and only the control modes, the predecrement mode, and the postin-
crement mode are valid. If the effective address is specified by one of the control
modes, the registers are transferred starting at the specified address, and the
address is incremented by the operand length (2 or 4) following each transfer. The
order of the registers is from data register 0 to data register 7, then from address
register 0 to address register 7.
If the effective address is specified by the predecrement mode, only a register-to-
memory operation is allowed. The registers are stored starting at the specified
address minus the operand length (2 or 4), and the address is decremented by
the operand length following each transfer. The order of storing is from address
register 7 to address register 0, then from data register 7 to data register 0. When
the instruction has completed, the decremented address register contains the
address of the last operand stored. In the CPU 32, if the addressing register is
also moved to memory, the value written is the decremented value.
If the effective address is specified by the postincrement mode, only a memory-to-
register operation is allowed. The registers are loaded starting at the specified
address; the address is incremented by the operand length (2 or 4) following each
transfer. The order of loading is the same as that of control mode addressing.
When the instruction has completed, the incremented address register contains
the address of the last operand loaded plus the operand length. In the CPU32, if
the addressing register is also loaded from memory, the value loaded is the value
fetched plus the operand length.
CPU32
REFERENCE MANUAL
Move Multiple Registers
Registers → Destination
Source → Registers
MOVEM register list, 〈ea〉
MOVEM 〈ea〉, register list
Size = (Word, Long)
Moves the contents of selected registers to or from consecutive
INSTRUCTION SET
MOVEM
MOTOROLA
4-99
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