Mitsubishi Electric MELSEC iQ-R Series Programming Manual page 301

Processing details
• These instructions decrement the 32-bit binary data in the device specified by (d) by one.
(d)
(d)+1 (d)+1
b31 b16 b15 b31
b0
··· ···
73500 (BIN)
-1
• When the DDEC(P) instruction is executed while the data in the device specified by (d) is -2147483648, 2147483647 is
stored in the device specified by (d).
• When the DDEC(P) instruction is executed while the data in the device specified by (d) is 0, -1 is stored in the device
specified by (d).
• When the DDEC(P)_U instruction is executed while the data in the device specified by (d) is 0, 4294967295 is stored in the
device specified by (d).
Operation error
There is no operation error.
(d)
b16 b15
b0
··· ···
73499 (BIN)
6 BASIC INSTRUCTIONS
6.2 Arithmetic Operation Instructions
6
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