1. Subtract one DEC/DECD
1. Subtract one DEC/DECD
1.1. Instruction description
The instruction (DEC) subtracts one from a 16 bit integer and produces a 16 bit result (OUT). Instruction (DECD) operates on 32-bit integers.
| Related registers | Description |
|---|---|
| M8169 | Operation overflow. |
| M8170 | The result of the operation is negative. |
| M8171 | The result of the operation is 0. |
1.2. The valid operands of the instruction
1.2.1. Single word Instruction(DEC)
| Input/Output | Data Type | operand | Description |
|---|---|---|---|
| IN | 16 bit integer | D/CV/TV/AI/AO/K/H/V/Z/FD, bit composite word (X/Y/M/C/T/S), local variable (LW) | Input |
| OUT | 16 bit integer | D/CV/TV/AO/V/Z/FD, bit composite word (Y/M/C/T/S), local variable (LW) | output |
1.2.2. Double Word Instruction(DECD)
| Input/Output | Data Type | operand | Description |
|---|---|---|---|
| IN | 32-bit integer | D/CV/K/H/FD, bit composite word (X/Y/M/C/T/S), local variable (LD) | input |
| OUT | 32-bit integer | D/CV/FD, bit composite word (Y/M/C/T/S), local variable (LD) | output |
1.3. Example
Command table:_
NETWORK 000
LD X000
DEC D0 D0 // D0 - 1 = D0
图1 DEC