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Guest steku

Disappointing results with Alps pulse rotaries

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Today the Alps rotary pulse switches I ordered arrived (similar to Knitter switches - at www.elfa.se/en/ you can find them by P/N: SRBM1L or 35-884-64). I tested them connected to two USB gamepad buttons and to simple gameport interface.As an application I used Leo Lacava

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Keyboard studio is an application able to assign sophisticated key press macros to joystick buttonsLook at:http://www.betainnovations.com/This site is owned by Leo Lacava - very friendly guy who is patient enough to answer all my newbie questions I asked him (Thanks Leo!)Steku

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Try with small cercamic capacitors in parallel to the outputs.Or small electrolytic in series to the outputs.I don't guarantee it will work, but it may help.

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Steku, I think the problem is as you say in the gamepad itself, the controller just doesn't expect pulses to come to it so fast & you will probably find it may not buffer the button presses either, can I suggest connecting it to a keyboard controller & see what the results are, alternatively if you have an FSBus system which I presume you don't try it on that or ask somebody to try it out for you that has an FSBus key controller working that can test it for you, I know FSbus buffers the pulses cause I see that here with the knitter switches. I have never tried a knitter on a game pad or keyboard.Cheers Glenn.You can check out my Simpit Project here:http://www.simhardware.co.nz/forums/viewtopic.php?t=33

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>Steku, >I think the problem is as you say in the gamepad itself, the>controller just doesn't expect pulses to come to it so fast &>you will probably find it may not buffer the button presses>eitherIt may also be the case the the single pulse is too fast, i mean it lasts too few instants, and it can't get recognized.

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Hi ErupsCould you recommend me type and parameters of these capicatiors?Steku

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Yesterday I received some advice from Leo Lacava (Thanks!)Alps switch performs much better with simplegameport interface than with USB gamepad! I tested it with gameportyesterday but not carefully enough. Using Leo's Keyboard Emulator withmultipliers and pool frequency set to high its even usable in FS (evenwith OBI)!!! It's still missing some inputs but it's much morecomfortable and realistic than using pushbuttons.I wonder how these switches will perform with other interfaces, like Leo Lacava's GammaRay 64 or 256 ant other.StekuBy the way: I disassembled one of these switches. Their constructionis really simple but it works (I'm really sad that I don't havedigital camera to show you this simple design). They aren't generatingfalse signals when touched - they are very stable indetents, but their drawback is very short pulse (pulse is generateddynamically when switch returns to detent). You can make the pulselonger by holding the switch when it wants to return to detent butwhen you are turning it normal way the switch is generating very shortpulses when it returns to detents. On every detent small mechanicalelement is "kicking" contacts (I wonder how many bounces are generatedby these kicks).

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Hi Steku,I was wondering about the contact bounce on this model. It seems that other people have had problems with various models of pulse rotary switches, but not all models(?). The very nature of their design suggests that contact bounce would be an issue. Contact bounce normally leads to a series of make and break actions from the switch. Perhaps this model was designed specifically to make a single massive bounce. This would avoid the multiple makes and breaks, but would result in only a very short pulse.Alternatively, the switch designers may have ignored the issue altogether. So perhaps the switch produces a lot of short pulses that really confuse the electronics.An experiemnt is to use the switch to trigger a chip called a monostable that can produce a fixed width pulse output. (For example a 74LS123) The LS123 output could feed into the gameport. If this resolves the problem, you would need a transistor (or equivalent) on the LS123 output if you want to drive a scanned matrix style input (like a keyboard).The downside of all this is, of course, that the whole reason for going with a pulse rotary switch was to avoid the decoder electronics needed with a rotary encoder, and this suggests the need for clean up electronics of roughly equal complexity.Mikewww.mikesflightdeck.com

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Steku,How did you interface it to the game port?I have the same switch and found the same problem when trying to use a gamepad. I then hooked it up to a keyboard controller and it works ok, but you still need to turn it slowly. I prefer standard rotaries when using a keyboard controller because you get the same performance or better and they are cheaper. Dave

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DaveI have one pair of Alps switch contacts connected as one button and second pair as another button of gameport interface.How can you use standard rotaries connected directly to keyboard controller (without any kind of decoder circuit)? :-eek For example to turn your heading bug clockwise you have to repeatedly push a key assigned to increasing heading bug (or radio frequency or OBI setting etc). With Alps or Knitter you can do this (you turn the rotary clockwise

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Steku,The easiest and cheapest way is to hack a keyboard controller and wire it up to 3 pin Hi/Lo pulse encoders. I used some panasonic ones from www.digikey.com . Once it is working, use FSUIPC to setup up the commands. I then set up a shift + key for fast turning capabilty. i.e. will turn the OBS course in 10 degree increments per rotary pulse. This makes up for having to turn the rotary slowly to avoid missed inputs.Example: To change OBS from 360 to 185, I just hold down on the keyboard and turn the rotary to select 180, -- only takes 18 clicks, then let go of shift and turn it 5 more.Read the last 5 or 6 posts on this link for more info on it and let me know if you have any questions.http://forums.avsim.net/dcboard.php?az=sho...ing_type=search

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Thanks DaveWhat a simple idea!I was considering hacked keyboard as my primary controller but I discovered other problem:I want to use two-position switches, for example for controlling lights (when you look at the switch position you immediately know if something is off or on). I was planning to assign controls in FSUIPC to two events: when the switch is pressed and when it

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Keyboards are matrixed:if you push two (or more) keys on the same column or raw, the controller cannot distinguish them, because it lacks data (in theory it is possible, but i think no encoder has such a logic).That's probably why you're haveing problems with your hacked keyboard.

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Steku,It depends on what you are trying to accomplish. Are you making a full cockpit or do you want an external radio/autopilot panel like the GoFlight products? I just wanted an external setup and somewhat generic so that it would allow me to use it for different aircraft in a desktop environment. That's why I used the keyboard hack and accepted the limitations of doing so.One way to handle the lights is to use a relay (there are some posts on this board about it if you search). It will allow you to flip the switch on or off and only send one keystroke for each toggle. This keeps the key from staying pressed the whole time. The only problem is that you will have to match the lights, etc. to the correct on/off state to match the switch each time start Flight Sim.Another reason the keyboard hack worked for me is because I am using FSLcd to display the radio freqs./autopilot modes/courses/and status of lights etc. To keep it simple, I just used momentary push buttons for the lights and stuff.

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>The downside of all this is, of course, that the whole reason>for going with a pulse rotary switch was to avoid the decoder>electronics needed with a rotary encoder, and this suggests>the need for clean up electronics of roughly equal>complexity.FSBUS uses a software "bounce" filter in the PIC code for switches and my ALPSes work pretty fine when wired to the KEY module.//Tuomas

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I know that FSBUS is a solution with great capabilities. But I don

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I have never heard that you need oscilloscope to tune FSbus !Perhaps what you should do is get a COM3 and a FSKey card from cockpitsonic.deNo need to do anything but order, pay and connect your stuff to it.

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Erups:>Keyboards are matrixed:>if you push two (or more) keys on the same column or raw, the>controller cannot distinguish them, because it lacks data (in>theory it is possible, but i think no encoder has such a>logic).Well, most PC keyboards don't have diodes built in, so the controller cannot distinguish certain combination of keys pressed at the same time. Often, it shows other keys as pressed, although they are not. This is usually called "ghosting".To prevent ghosting, you add a diode for every switch in the matrix. Thats how most home cockpit interface solutions do it, like FSBUS, ...The diodes basically prevent the current flowing in unwanted directions.Here is a circuit of mine (512 input key matrix):http://cockpit.varxec.de/electronics/img/PICkeymatrix512.png the detail cutout in the upper left hand corner shows how the diodes are hooked up. Manuel

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