|IN||VB, IB, QB, MB, SB, SMB, LB, AC, Constant, *VD, *AC, *LD||BYTE|
|OUT||VB, IB, QB, MB, SB, SMB, LB, AC, *VD, *AC, *LD||BYTE|
|Memory Ranges||ENO||Errors||Instruction Support for S7-200 CPUs||SIMATIC/International Mnemonics|
|The Increment Byte and Decrement Byte instructions add or subtract 1 to or from the input byte (IN) and place the result into the variable specified by OUT.
Increment and decrement byte operations are unsigned.
In LAD and FBD: IN + 1 = OUT
IN - 1 = OUT
In STL: OUT + 1 = OUT
OUT - 1 = OUT
Error Conditions that Set ENO = 0:
SM1.1 (overflow), SM4.3 (run-time), 0006 (indirect address)
These instructions affect the following Special Memory bits:
SM1.0 (zero); SM1.1 (overflow)