# Logical Switches These are logic switches that are used to compare values and combine various conditions. The first "operation" column lists a few arithmetical, logical and differential operations. In arithmetical ones a and b represent variables, x represents a constant. Variables can be every source, i.e. all those available in mixers, plus the 5 global variables and all telemetry values. In logical operations the available sources are all physical and other custom switches. Differential functions compare the variation of a variable since last match to another value. * a\~x: active when variable a is approximately equal to constant x (hysteresis added, as comparing a stick's value for example would pretty much never trigger an exact match) * ax: Active when variable a is smaller resp. greater than constant x * |a|x: Active when the absolute value of variable a is smaller resp. greater than constant x * ab,a=b: See above, but with 2 variables * AND, OR, XOR: Logical and, or, exclusive or between 2 binary inputs * d>x, |d|>x: Active when the selected variable, respectively its absolute value has changed by more than x since last time. For example, d>x Alt 10 would trigger once every time Altitude goes up by 10m. |d|>x Alt 10 would trigger once every time Altitude goes up OR down by 10m. * TIM: A timer, TIM 0.5 2.0 would be active for 0.5s, inactive for 2s, and repeat. Custom switches offer 3 more parameters: An extra AND condition (if selected, must be on for the custom switch to become active), a Duration parameter (the minimum time a custom switch will be active for even if its conditions become false instantly), and a delay parameter (that affects both activation and deactivation). See the title bar header to see the function of the field the cursor is on. A long press of the ENTER key on a custom switch's label will bring up a popup menu that allows you to copy/paste/delete an entry for more convenient entry of similar settings. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://doc.open-tx.org/manual-for-opentx-2-2/software-overview/model_menus/logical_switches.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.