Sys 3 board - Rotary Switch (dumb question)

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Sys 3 board - Rotary Switch (dumb question)

Post by pmillerrusso »


THis is probably a dumb question but I am looking at the SYs 3 board and trying to understand something. If I connect a rotary switch that has four position am I essentially using up 4 of the 32 'switches', in other words the board supports 8 4-position rotary switches? Am I correct or incorrect?



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Rotary Selectors

Post by pcos »

Rotary Selectors are "Switches" in the sense that each "Step" can be used and will count as a "Switch".
Terminology might be different here but I think you have the right idea.
Part of what needs to be watched when planning your interface requirements is making sure you are wiring "required" items....
A term that many builders are learning is "Realistic Representation".
Panels that have all the hardware in place but are not functional.
Examples are Climate Control Panels..
Imagine counting the 8 steps of the "passenger" Temperature Control....
Not sure you need that interfaced...
unless you have passengers!
The SYS1 is able to handle 64 switch inputs.. ( plus 256 LED outputs)
The new SYS2 will be out next week and also handles 64 Switch inputs.

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Post by vidarf »

Not to forget: for a 4-position rotary switch, you only need to use 3 inputs. You just define position 1 as "off" state, and since the SYS boards can "see" the state of the switch - magic happens! :)

And do notice the advice Peter is giving here: not all switches needs to be interfaced! For example, in a 737 overhead you do not need to interface the navigation and displays switches right above the fuel panel...

This way you save inputs. Another example: for the start switches, you don't need to interface the CONT and FLT states - only the GND position is needed (so you can start your engines). The other positions is just needed for procedure training anyway.

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Post by SWeker »

The picture in this post way help you understand rotary's.... ... php?t=2970
Steve Wekarchuk

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Post by pmillerrusso »

Thanks everyone for the great replies...

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