HEIDENHAIN TNC 306 Technical Manual - Manual (Page 318)

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TNC 416/TNC 406/TNC 306 Commands 3/2000
3.1.2 LOAD NOT (LN) LN
Abbreviation for the PLC-Editor: LN (LOAD NOT)
Logic Byte/Word Double Constant
Execution time [µs] 1.6 2.4/2.0 2.2 1.8
Number of bytes 6 8 6 8
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 inputs I4 and 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: Input I4 = 0
Input I5 = 1
Output O2 = ?
Line Instruction Accumulator contents Operand contents
Bit 31 . . . 7 0
... x x x x x x X x x x x x x x
1 LN I4 ... x x x x x x 1 x x x x x x x 0
2 A I5 ... x x x x x x 1 x x x x x x x 1
3 = O2 ... x x x x x x 1 x x x x x x x 1
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.