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CHAPTER 3 FEATURES OF THE ARCHITECTURE AND MEMORY MAP
(b) Specific address bit register indirect addressing (pmem.@L)
In this addressing mode, the bits of peripheral hardware I/O ports are indirectly specified using a
register to allow continuous manipulations. This addressing mode can be applied to data memory
addresses FC0H to FFFH.
In this addressing mode, the high-order 10 bits of a 12-bit data memory address is directly specified
in the operand, and the low-order two bits and bit address are indirectly specified using the L register.
Thus the use of the L register enables 16 bits (four ports) to be continuously manipulated.
This addressing mode again enables bit manipulation regardless of MBE and MBS setting.
Example Pulses are output on the bits in the order from port 4 to port 7.
MOV L,#0
LOOP: SET1 PORT4.@L ; Bits (L1-0) of ports 4 to 7 <– 1
CLR1 PORT4.@L ; Bits (L1-0) of ports 4 to 7 <– 0
INCS L
NOP
BR LOOP
P40
P41
P73
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