Article Details
- Title
- Latches
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- None
- Sequence
- 0
- Body
- Latches are simple binary objects that are either set or not set, or on or off, or 1 or 0, or true or false. They are used for any miscellaneous information that needs to be stored about the interlocking. Latches can optionally have two conditional statements, one to set the state, and another to clear the state. Only one transition may be performed per interlocking cycle so if both conditional statements evaluate to true, only one state transition will take place. If both conditional statements are true, it is undefined as to which state the [b]Latch[/b] will be, and inference should not be assumed from past behaviour. Latches can also be set or cleared by commands in other logic elsewhere in the interlocking, or even a different interlocking with cross-interlocking commands. Certain other actions, such as TRTS latches on signals, can also cause state transitions. [b]TRTS Latches[/b] While TRTS latches are [b]set[/b] by trains acting on [b]Signal[/b] objects, the interlocking is required to unset the latch when appropriate. Typically this is when either the signal to which it applies shows a proceed aspect, or all the tracks in the platform become clear. Some installations have a button on a panel to reset all TRTS latches, though this is rare. [i]Example[/i] (unset conditions) Tplatform.c or S456.isoff
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- 2
- Created
- 30/07/2025 at 16:42
- Updated
- Never
- Created By
- CajonRail
- Updated By