10
DEVICE EXPLANATION
10
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10.2 Internal User Devices
10.2.12 Data register (D)
10.2.12 Data register (D)
(1) Definition
Data registers are memory devices which store numeric data (-32768 to 32767, or
0000
H
to FFFF
H
).
(2) Bit configuration of data register
(a) Bit configuration and read and write units
Data registers, which consist of 16 bits per point, read and write data in 16-bit
units.
POINT
Data register data are handled as signed data.
For HEX (hexadecimal), 0000
H
to FFFF
H
can be stored. However, since the most
significant bit is a sign bit, the range of a value that can be specified is -32768 to
32767.
(b) When data register is used for 32-bit instruction
If the data registers are used for 32-bit instructions, the data will be stored in
registers Dn and Dn + 1. The lower 16 bits of data are stored at the data register
No. (Dn) designated in the sequence program, and the higher 16 bits of data are
stored in the designated register No. + 1 (Dn + 1). For example, if register D12 is
designated in the DMOV instruction, the lower 16 bits are stored in D12, and the
upper 16 bits are stored in D13.
Two data registers can store a range of numeric data from -2147483648 to
2147483647 or from 0
H
to FFFFFFFF
H
. (The most significant bit in a 32-bit
configuration is a sign bit.)
(3) Holding of stored data
The data stored in the data register is held until the other data is stored.
The data stored in the data register is initialized when the PLC is powered OFF or the
CPU module is reset.
Figure 10.37 Bit configuration of data register
Figure 10.38 Data transfer by 32-bit instruction and storage destination
Dn
b15
to
b0
The most significant bit is sign bit.
K500000 D12
DMOV
D13
D12
Processing object: D12, D13
Upper 16 bits Lower 16 bits
