gentlemen...g'day
there is a requirement to not only have a rotary switch operate directionally, but to also do that to predetermined positions (accurate # of steps up and down). e.g. OFF -1 - 2 - 3 etc. examples are (on the 737NG) the Autobrake, Wiper Controls, Panel Lights, Pressurisation Auto/Man/Alt and even the Starter Switches.
so i'm sat here wondering how i can operate these switches exactly. hmmm, has to be an answer. and there is. rotary encoders were the easy answer for directional control, but they did not give me the exact switch 'Click Position'.
2 bit gray encoders are basically two continuity circuits made to contact with a 'common' in a predetermined arrangement as they rotate. it's this arrangement or pattern that the control (either hardware or software) sees and acts upon. it doesn't matter what your control is, it is looking for this 'switch change state' to act upon.
so i decided to replicate the switching behaviour of a 2 bit gray encoder with a 2 pole 6 way rotary switch. result is excellent. it works, it works well and i thought it was worth sharing. see http://www.737ng.co.uk/help.htm for how i did it.
i'll upload this later in the week when i get my head round how to do it. hope this gives lots of you things to think about.
have a good one tomorrow, i will (me and my soldering iron)
best regards as always ... ian
