HEIDENHAIN TNC 306 Technical Manual - Manual (Page 316)

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TNC 416/TNC 406/TNC 306 Commands 3/2000
3 Commands
3.1
Load and Assign Commands
3.1.1 LOAD (L) L
Abbreviation for the PLC-Editor: L (LOAD)
Logic Byte/Word Double Constant
Execution time [µs] 1.2 2.0/1.6 1.6 1.2
Number of bytes 4 6 4 6
Logic execution with LOAD command
Operands: M, I, O, T, C
Operation:
The addressed operand is copied into the 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 A, O, XO are used at the start of a logic chain, however this should
only be used when compatibility with the TNC 355 is required.
Example:
Inputs I4 and I5 are to be gated with AND and the result assigned to output O2. Thus the logic state
of input I4 is loaded into the Accumulator to enable subsequent gating commands.
Initial state: Input I4 = 1
Input I5 = 0
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 L I4 ... x x x x x x 1 x x x x x x x 1
2 A I5 ... x x x x x x 0 x x x x x x x 0
3 = O2 ... x x x x x x 0 x x x x x x x 0
Line 1: The 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.