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New Flight Deck Solutions 7 segment LEDs

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"Specially if you have multiple LCDs compared to lots of 7segments. Each 7segment requires 9 wires."Well, no, not actually. First, 9 wires includes the decimal, which is always off except for one digit, where it's always on - just wire that one segment to power and forget it.As for the other wires, you can actually connect all the wires to the same segment of several LCD's in series, and only connect the common anode (or common cathode) individually. This multiplexing allows several LCD's to be run by a much lower number of outputs... 8 outputs for one LCD, 9 for two, 10 for three, and so on. For reasonable numbers of LCD's visual persistance prevents any visible flickering.Richard

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Guest PoRrEkE

*quote*"Specially if you have multiple LCDs compared to lots of 7segments. Each 7segment requires 9 wires."Well, no, not actually. First, 9 wires includes the decimal, which is always off except for one digit, where it's always on - just wire that one segment to power and forget it.As for the other wires, you can actually connect all the wires to the same segment of several LCD's in series, and only connect the common anode (or common cathode) individually. This multiplexing allows several LCD's to be run by a much lower number of outputs... 8 outputs for one LCD, 9 for two, 10 for three, and so on. For reasonable numbers of LCD's visual persistance prevents any visible flickering.*/quote*Are you confusing LCD's with 7-segment led displays ?7segment led displays requires 9 wires, from which 1 is GND, so 8 wires per DIGIT. If you got a nav radio (both stby and the active) that makes 1 GND + 80 I/O's. (1 GND + 1 steady "1" for both decimal points + 70 I/O's if you want) That is just for 1 radio, total 72 wires. For 2 radios: 142 wires.Compare this to LCD's. (like this one: http://www.crystalfontz.com/products/0802a...802A-YMC-JP.jpg )They need each power & GND. For the input each LCD needs 1 I/O to let the LCD know which one you address the data too which is on the 8+2 wire bus. So for 1 radio: 11 wires. For 2 radios 12 wires.Or am I wrong and was your explaining not about LCD's as you wrote but about 7-segment leds ? It's been quite a while since I last worked with my Photon output cards so I'm not quite sure anymore.If it is true that you need per 7-segment extra only 1 wire extra you'd end up with 8 for first segment, 9 for 2, 12 for 5 and 17 for 1 radio. Then 27 for 2 radios. Which is more than 12 :DI win anyhow :(And I can't understand why not more people are interested in LCD's. Simply because in real they use LCD's anyhow.

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Sorry, a typo which I then just continued... I meant 7-segment LED's."7segment led displays requires 9 wires, from which 1 is GND, so 8 wires per DIGIT."Which is what I was saying that you don't need to do. You need only one wire for each segment of ALL digits, plus one wire for the common anode (or common cathode) of each digit.Here's an example....http://forums.avsim.net/user_files/105251.jpgAs you see, this five-digit by 7-segment LED uses only a total of 12 wires. For 10 digits, you'd need 15 wires - although 10 is getting up towards the upper limit of what you can do with multiplexing without seeing the digits flicker.Richard

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Guest PoRrEkE

So I got it righ in the end.Conclusion:For an entire sim, using 7-segment LEDs will require something like 85 outputs ore a lot more.Compare this same calculation (HDG+CRS+IAS+ALT+NAV+NAVsby+COM+COMsby+ADF+ADFsby) to what you need of outputs with LCD's .. you will need 20 outputs. No more, no less.That is very much less wires you have to buy for starters. That is a lot less confusion concerning the wires. That is the same price for the hardware and even LCDs are cheaper if you compare to 7-segments WITH a pcb to mount them on.I realy don't see why not more people opt for this approach. Only thing is that there is no real interface for it yet, though it is comming together in the form of PHCC (which btw also have other advantages).

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>That is very much less wires you have to buy for starters. >That is a lot less confusion concerning the wires. That is>the same price for the hardware and even LCDs are cheaper if>you compare to 7-segments WITH a pcb to mount them on.>>I realy don't see why not more people opt for this approach. >Only thing is that there is no real interface for it yet,>though it is comming together in the form of PHCC (which btw>also have other advantages).IOCards apparently at least had support for those - and since it is not wired via parallel port directly, one could add a lot more of those.But I am not sure what their plans are currently about supporting those LCDs.//Tuomas

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Guest PoRrEkE

Well I chose to go for PHCC and I might switch to PHCC entirely and get ridd of my Hagstrom and Photon stuff, who knows.I am expecting my mother card to arrive here shortly with a kit so that I can start to assemble. Very exciting :)After that I will have to wait for the USB upgrade card because I don't have a serial port on my laptop. I intend to use my laptop for the interfaces & the software for them and chanel all IO trough fsuipc to the other computers.Then also later arriving is the boards which will interface the LCD's.I don't have the LCD's yet :( I was expecting them via someone but haven't heard from him for a while.

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Guest twabi2

Poreke, I still have an extra PHCC-USB expansion here, unsoldered...do you want it?If you're affraid of soldering the SMD chip, I can do it for you, as I did it with my USB (perfect at the first try)

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Guest PoRrEkE

You had 2 ?And why does a chip needs soldering ? I'm not affraid of soldering anything, unless it is very small :DThings that should get hot are no problem, I believe I can solder fast & precise enough .. but if you want to do it .. sure.I've sent an e-mail to ask Manuel if it's OK if I go for this one.All that is left to find is then the LCD expansions and the LCD's themselves.After that .. lotza programming to do :D

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"For an entire sim, using 7-segment LEDs will require something like 85 outputs or a lot more."Well, that depends on how you're going to drive them. I'm driving mine from some PIC's, so I'll actually only be using 3 outputs to pass serial info to the PIC's, which will then drive the LED's.I actually only decided to go this route because I picked up a bunch of these....http://forums.avsim.net/user_files/105345.jpghttp://forums.avsim.net/user_files/105346.jpgon eBay for next to nothing.Richard

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Guest twabi2

Well, the chip is a real small SMD and Manuel blew his first one, I ordered a new one for him :)There's like a 0.5mm space between each leg, but if you've got some experience it should be no problem

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Guest PoRrEkE

Contact me pvanagt ad skynet dot be

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