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Chapter 2. Functions
2-11
2.3.8
Data register : D
The D area is used to store numeric data. Each data register consists of 16 bits (1 word) which
is the unit of data read and write.
The data resister number designated by the double-word instruction holds the lower 16 bits and
the designated data register 1 holds the higher 16 bits.
Example)
D51
D50
h1234
h5678
The D area except latched area assigned by parameter setting will be cleared as 0 when the
CPU is switched on or turned to RUN mode.
2.3.9
Indirect assignment data register : #D
#D is used for indirect addressing of the D area. The contained value of data register assigned
with ‘#’ symbol points the real address of data register at which the result of operation is stored.
If #D is used with a double-word instruction, the lower 16 bits will stored at the data resister
number designated by the contained value of #D, and higher 16 bits will stored at the data
resister 1.
Example)
DMOV h12345678 D050
High 16 bits Lower 16 bits
MOV D000 #D1023
h7893
h03E8(1000)
(Hex value)
(No. of data register)
D0000
D1000
D1023
The actual data movement
Indirect addressing (#D0123)
If the value of data register assigned at # D exceeds the physical address range of D area, the operation error
flag(F110) will be set and the relevant instruction will be ignored.
Remark