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Gekkibi
18th February 2008, 01:19
I have an interesting request. I am making authentic cockpit, and have modelled some key functions. If there is a willing coder who likes to help me for any reason, don't hesitate to contact me via private message and/or repost to this thread. Don't start to code yet, I can explain my project with more details. This is just a scratch I typed in here 3:18AM, because I was having problem with sleep. :)

I need a program what sends certain telemetric information from outgauge to LPT-port (Like http://www.lfsforum.net/showthread.php?t=13973&highlight=gear+indicator , but I need more options).

Nastiest thing is that it must also send synchronization clock signal using 2 pins (Four combinations). This changes every X ms (Adjustable via config-file).

When the sync-signal is 0&1, it sends speed using PCD-code ("100's" only in two digits, that would make max speed of 399 km/h. This is due to the limitation of LPT-port (12 usable pins, and 2 are for sync-clock).
So, for example the pins would be like this: 0101 0110 1001. It would mean 169km/h (Remember, first two digits are sync-signals).

When the sync-signal is 1&0, it sends revolutions using PCD-code (4 Digits). That would allow to have 15 different tresholds (Because 0000 is true 0, and no leds would light up).

When the sync-signal is 0&0, it sends different kind of signals to all 10 pins (For example, signal lights, handbrake light, reverse light, shift light, stall light, etc).

When the sync-signal is 1&1, it sends gear number (Just like GI by Vladimir Kadlec). Gear number would only need 7 pins (As 7-segment display only has 7 segments. DUH! ;), so the rest (three pins) can be used for additional lights (Signal lights etc).

There should be some kind of config.cfg, where I can change what conditions activates what pin (Just like in Vladimir Kadlec's GI).

Kada_CZ
18th February 2008, 11:12
Hi Kalle,
consider also other option, with some microchip able to communicate over USB. E.g. this (http://forum.rscnet.org/showthread.php?t=277873) by MMos (the rsc site is down at the moment), it's based on pic18f4550 (http://pic18fusb.online.fr/wiki/wikka.php?wakka=UsbBootload). It's more complicated to build it, but you whould have a lot of on/off pins as well as PWM outputs for tacho, speedo, etc... There is support for LFS and the MMos's hardware.

I'm not sure, if multiplexing wouldn't be too slow. I mean, you would notice "lags" between e.g. tacho in LFS and you hardware.

Gekkibi
18th February 2008, 11:45
Sounds pretty hc to me. But I'll give it a try.

Uploaded some pics of my project if you are interested:

Driving light logic (Including external lights)
http://www.students.tut.fi/~nummelak/projektityo/drivinglightlogic.JPG

Rev-meter logic
http://www.students.tut.fi/~nummelak/projektityo/revmeterlogic.JPG

Speedometer logic
http://www.students.tut.fi/~nummelak/projektityo/speedometerlogic.JPG

External lights
http://www.students.tut.fi/~nummelak/projektityo/externallights.JPG