Load Not (Ln); Logic Execution With The Load Not Command - HEIDENHAIN TNC 415 Technical Manual

3.1.2 LOAD NOT (LN)

Abbreviation for the PLC-Editor:
Execution time [µs]
Number of bytes

Logic execution with the LOAD NOT command

Operands: M, I, O, T, C
Operation:
The complement of the addressed operand is loaded into the Logic Accumulator. A load command is
always used at the start of a logic chain in order to enable subsequent gating commands. The same
function is achieved when the gating commands AN, ON, XON are used at the start of a logic chain,
however this should only be used when compatibility with TNC 355 is required.
Example:
The inverted logic state of Input I4 and Input I5 is to be gated with AND and the result assigned to
Output O2. Thus the inverted logic state of Input I4 is loaded into the Accumulator to enable
subsequent gating commands.
Initial state:
Line Instruction
Bit
1 LN I4
2 A I5
3 = O2
Line 1: The inverted operand contents are loaded into the Logic Accumulator.
Line 2: The contents of the Logic Accumulator and Input I5 are gated with AND.
Line 3: The gating result is assigned to Output O2.
7-38 TNC 407/TNC 415/TNC 425
LN (LOAD NOT)
Logic
0.2 to 0.7
6
Input I4 = 0
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 1 x x x x x x x
... x x x x x x 1 x x x x x x x
3 Commands
Byte/Word Double
0.5 to 1.6 0.5 to 0.7
8 6
7 0
Constant
0.2 to 0.3
8
Operand Contents
0
1
1
01.98