5 greater than or equal tol[ ] (>=[ ]), 6 not equal to [ ] (<>[ ]) – HEIDENHAIN TNC 407 (243 020) Technical Manual User Manual
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3.8.5 GREATER THAN OR EQUAL TOL[ ] (>=[ ])
Abbreviation for PLC Editor:
>= [ ] (GREATER EQUAL [ ])
Logic
Byte/Word/Double
Execution time [µs]
----
0.5 to 0.8
Number of bytes
----
6
Operands: none
3.8.6 NOT EQUAL TO [ ] (<>[ ])
Abbreviation for PLC Editor:
<> [ ] (NOT EQUAL [ ])
Logic
Byte/Word/Double
Execution time [µs]
----
0.5 to 0.8
Number of bytes
----
6
Operands: none
Function of parentheses with comparison commands:
The execution sequence in a ladder may be altered by the use of parentheses. The "open-
parentheses" command loads the contents of the Word Accumulator onto the Program Stack. The
Accumulator is now available for the calculation of intermediate results.
The "close-parentheses" instruction initiates the gating of the buffered value from the Program Stack
with the content of the complete Word Accumulator. The result is loaded again into the
Accumulator. The maximum nesting depth is 16 parentheses.
A direct transition from Word to Logic execution takes place with comparison commands. If the
comparison condition is "true", the Logic Accumulator is set to "1". If the condition is not fulfilled, the
Logic Accumulator is set to "0".
Example:
Initial state:
Constant
= 1000
(decimal)
Doubleword D12 = 15000
(decimal)
Doubleword D36 = 10
(decimal)
Output
O15 = ?
The Accumulator contents and operand contents are shown in decimal notation. The ten-position
Accumulator thus permits the maximum possible Accumulator content of 2 147 483 647.
The Accumulator is again represented in binary notation after program line 5, as the transition to
logic execution occurs here.