Exclusive Or; Logic Execution With The Exclusive Or Command - HEIDENHAIN TNC 415 Technical Manual

3.3.5 EXCLUSIVE OR (XO)
Abbreviation for the PLC-Editor:
Execution time [µs]
Number of bytes

Logic execution with the EXCLUSIVE OR command

Operands: M, I, O, T, C
Operation:
This command functions in different ways according to its position in the program:
a) At the start of a logic chain the command functions as an L command, i.e. the logic state of the
operand is loaded into the Logic Accumulator. This is to ensure compatibility with the TNC 355
control which did not have the special L command.
In PLC programs for the TNC 407/TNC 415 a logic chain should always be started with a load
command (see L, LN, L–).
b) Within a logic chain the contents of the Logic Accumulator and the logic state of the operand
(M, I, O, T, C) are gated with EXCLUSIVE OR.
The result of the operation is stored in the Logic Accumulator.
Example:
Input I4 and Input I5 are to be gated with EXCLUSIVE OR and the result assigned to Output O2.
Initial state:
Line Instruction
Bit
1 L I4
2 XO I5
3 = O2
Line 1: The operand contents are loaded into the Accumulator.
Line 2: The contents of the Logic Accumulator and Input I5 are gated with EXCLUSIVE OR.
Line 3: The gating result is assigned to Output O2.
01.98 TNC 407/TNC 415/TNC 425
XO (EXCLUSIVE OR)
Logic
0.5 to 0.7
6
Input I4 = 1
Input I5 = 1
Output O2 = ?
Accumulator Contents
31 . . .
... x x x x x x X x x x x x x x
... x x x x x x 1 x x x x x x x
... x x x x x x 0 x x x x x x x
... x x x x x x 0 x x x x x x x
3 Commands
Byte/Word Double
0.5 to 0.7 0.5 to 0.7
6 6
7 0
Constant
0.2 to 0.5
8
Operand Contents
1
1
0
7-61