Working with rotary switches

[matta757]

Hi everyone,

I am really struggling here to figure out something with rotary switches. I will do my best to try to explain my desired outcome in the hopes that someone might actually be able to figure out what I am trying to do!

I want to create a working setup for switches on my 757 overhead for functions such as APU, Engine Start and Passenger Signs. I am using the PSS 757 software, not sure if that is important.

I am thinking that rotary switches are my best (only?) option for creating these switches on the panel (please tell me if I am incorrect...).

My problem is figuring out whether or not I will be able to program them to work correctly. Do rotary switches register the "position" of the switch, or do they register the "movement" of the switch? The reason I ask is that for programming switches such as engine start with the PSS software, the only options are "APU Increase = F7" and "APU = F8" (using example button assignments on the keyboard).

If they register the position, for example OFF, ON, START then I am assuming there is no way that I can program them using the PSS software. But if they register movement from one position to another, would it be possible to program them?

For example, say the switch has those 3 positions; could I program movement from position 1 to 2 as F7 (increase), movement from 2 to 1 as button F8 (decrease), movement from 2 to 3 as F7 (increase) and movement from 3 to 2 as F8 (decrease)?

Also, when using the BUO836X, does the rotary switch hook up to the panel as a button or an axis?

I don't know if this makes any sense, and so if it doesn't, I apologize. If you think you know what I might be trying to do, any help would be greatly appreciated!

Best regards,

Matt

[autocadplease]

Rotary switches are "position" switches. If you are after only movement (increase/decrease) just use a rotary encoder - just make sure your card can handle encoders (BU0386X does).

Hooking rotary switches to the BU0386X: Each terminal on the rotary would be like a switch / button. So when you turn the rotary switch to the desired position the corresponding terminal will make contact and complete the circuit. Note: You can solder terminals together if you want more than one position to do do the same thing.

Ian's site has lots of info http://www.737ng.co.uk/technical.htm

[matta757]

Hi Grant,

Thank for your insight. I guess a rotary encoder is probably what I need. I am assuming that is different than a pot though? I need to be able to assign whatever I use to a key press (like F7) through FSUIPC to get it to work. Can rotary encoders be programmed as key presses? I tried to program an axis on a joystick as a key press, and either I did it wrong or it doesn't work.

Matt

[fordgt40]

Matt

As Grant suggested, you should look up Ian Sissons website. He has examples of what you are trying to achieve ie using a rotary switch as a pseudo encoder linked to FSUIPC via Leo Bodnar`s card.

David

[ian@737ng.co.uk]

hello matt..........
go here http://www.737ng.co.uk/technical.htm
in the right hand column is an item 'how to make an encoder from a rotary switch'
exactly what you want to do....
good luck, best regards and merry christmas.... ian

[autocadplease]

I guess a rotary encoder is probably what I need. I am assuming that is different than a pot though?
Yes, it is.


Can rotary encoders be programmed as key presses?
Yes, through FSUIPC.


I tried to program an axis on a joystick as a key press, and either I did it wrong or it doesn't work.
I don't think that will work because an axis is usually a pot.

[Jylhami]

I believe, that biggest broblem in your setup is the fact that there is no different key for each position.
There is a possibility, that the switch has been moved when the electronics is off and then you loose the position information.

I have the same problem now when building hardware to the Reality XP's WX500 weather radar.

BR:Mika

[matta757]

Thank you to everyone for your responses. As usual, you guys have really come through! Ian, this tutorial on your website is EXACTLY what I need, so thanks again everyone for pointing me in the right direction!

Matt

[matta757]

Hey all,

Just another question this time about supplies. I am looking at rotary switches (obviously) but had a few questions to ask.

First of all, I am looking at this switch from FDS http://www.flightdecksolutions.com/prod_info.php?id=74

What does it mean when they say "45 degree indexing" or "30 degree indexing"? Is that the amount of degrees for each turn? Also, what does they mean when they say "User Defined Steps"? It also says 2 to 8 steps... how does one set the amount of steps?

Regards,

Matt

[fordgt40]

Matt

"Is that the amount of degrees for each turn" - Yes

"how does one set the amount of steps?" - there is a detachable metal ring around the shaft which has a "tang" which locates in whatever hole suits the number of switch positions you require. It is easier to implement than explain

David

[matta757]

Matt

"Is that the amount of degrees for each turn" - Yes

"how does one set the amount of steps?" - there is a detachable metal ring around the shaft which has a "tang" which locates in whatever hole suits the number of switch positions you require. It is easier to implement than explain

David

David,

I understand what you are saying now. So can the switches from FDS be used with the tutorial on Ian's website?

Regards,

Matt

[fordgt40]

Matt

No! - you must use a two pole 6 way rotary switch as described in Ian`s tutorial. Suggest you check Mouser.com or other large supplier. Alternatively, as Ian will get a notification of this post, he may be able to give you a product reference

David

[matta757]

Alright guys, I have another question now that I am starting to wire.

The engine start switches in a 757 turn left to GND to start but once the engine starts, they snap back one click to the right to AUTO. I don't want to attempt to make the switch automatically "snap" back to AUTO, but I was wondering if there is a way to wire the rotary switch so that I can switch the knob back to AUTO (once the engine starts) but WITHOUT the switch respond in flightsim. This is because once the switch snaps back to AUTO in FS but my actual switch is still on GND and if I turn it to put it on AUTO, the game will read that as me moving it from AUTO to FLT. Does that make sense? Is there a way to wire a 2-pole rotary switch to make this work?

Regards,

Matt

[deering]

Hello Matt.



.... moving it from AUTO to FLT.


Can you clarify how many switch positions you are mapping? Does the switch not go from AUTO to OFF in the conditions you described?

Jim.

[matta757]

Hi Jim,

The switch positions are as follows from left-right: GND-AUTO-OFF-CONT-FLT

So I meant to say that when the engine has started IN FLIGHT SIM and the switch snaps back to AUTO in the game, on my physical panel the switch will still be on GND. If/when I turn the switch from GND to AUTO (which is where it would move to on the real airplane) the game will recognize that as moving the switch from AUTO to OFF because in the game the switch is already on AUTO and not GND.

Does that make more sense?

My thought process is would it be possible then to wire the switch so that the AUTO position does not have a response in the game?

Regards,

Matt

[ian@737ng.co.uk]

hi matt.........
if this is for the starter switch and you dont want the starter switch to be seen turning back, then why use an encoder? just simply wire the rotary switch to see the GND (and FLT if you want) position.
i cheat (I learned very early on that compromise is one of the best words i know), i have wired the starter switches so they contact at the GND position and then i've 'tee'd' a connection to the FLT position. so in essence, i have a connection at GND and FLT (the same one). then i send the signal thru a BU0836X card and use an engine starter command in FSUIPC. sorry i'm not near the cockpit at the moment so i can't tell you which command and it's such a long time since i did it that i can't remember. but i know it's not autostart because i have to make sure my fuel levers are in idle or the engine does not start. you can even record a mouse macro to do the job for you if your panel supports them.
sorry i didn't realise what you wanted to do when you contacted me, i assumed you wanted an encoder for a 'special switch' like the wipers or autobrake.
BTW, any cheap rotary switch will do as long a it has the correct indexing for your panel (30 or 45 degrees).
good luck and regards ... ian

[matta757]

Hey Ian,

Actually this question came up AFTER you had sent me the other info. Your answer to my other question was a big help too.

Following your idea about just wiring the individual switches, what wires touch which contacts and so forth? I am using a 2-pole, 30 degree index. Do I wire one contact with one position and the other contact with a different position and then attach them to the board?

Matt

[deering]

Matt, that's how I thought it must be. Follow Ian, he's leading you in the direction I was about to send you. Jim.

[ian@737ng.co.uk]

hi matt.......
leave it with me, i'll mail you an explaination in the morning (dinner time in the UK and the bride is telling me if i dont go now, my dinner will be in the dog :o
rgds ... ian