This is another query about a possible electronics project. Having built a few circuits based on guidance from the BBS, I am emboldened!

I want to start work on the “perfect” rally computer. This could take 2-4 years to become functional and, like many things, may never really be done. Why? Well, traditional dedicated “A box” rally computers like Timewise and Alfa function very well but are closed systems – they use custom PROMs that aren't really accessible by owners and they rely on minute-by-minute management during rallies (enter new CAST/speed). At least one person has written a laptop-based rally computer, but, as we decided this past weekend, it suffers from the lack of a simple interface -- hitting the right function key when bouncing through a hairpin can be tough! (and the perfect LCD display does not exist yet). So, what I'd like to build is something that combines the good features from each – the ability to pre-enter complete rallies on a laptop then upload to rally computer combined with a simple, dedicated “A” box interface with big knobs, switches, and red LED counters. The attached graphic shows the general layout that I have in mind.

A few parts are not complicated. For instance, I built a VFD driver's display with serial input that was the one piece of our setup that worked without a hitch last weekend. Others, well, here's where my questions begin....

Driver Guide:

This is something I dreamed up – just LEDs that show yellow if on time, red if you need to slow down, green to speed up. It would not be powereed when ignition off, so power consumption not an issue. In my mind, it would receive 2 kinds of messages (from the main computer): Illumination/dim level (0-10) and LED pattern (which of 11 LEDs to illuminate at that moment, say in binary). As simple as can be – decisions about what 4 green LEDs mean can be made in the main computer/program and could be changed as desired. So, I guess my question is whether there is anyplace to start in the way of a pre-built board/circuit/PIC for this component.

Sensor pulse input:

This would have a 2-wire interface for up to 4 drop-to-ground pulse sensors which could range from 0.1 to 12 volts. The current pulse count for each sensor would be stored on the device until cleared with something deliberate like a shorted jumper. Each counter would read up to 9,999,999 this would be good for around 2000 to 5000 miles before reset depending on sensor mix. This small box would be connected to unswitched power – never powered off. So power consumption would be a critical issue. The counter storage method should be able to tolerate loss of power, though, in case of something like main battery fuse failure or maintenance that requires disconnect of ground/earth. The idea of this is to allow bad things like reboot to happen to main rally computer without messing up basic counters. Oh, and it needs to talk to the main computer. I indicated ethernet, but expect it could be serial – just a simply formatted counter message like: “0000322,0000822,0000000,0000833” All speed calculations would be performed (I think) on main box where odo factors are stored, but it could be useful to send factors to the sensor unit so that actual speeds could be returned along with counters.

So, ultra lower power consumption, separate persistent registers for each counter, ability to send (and maybe receive) via ethernet or serial. Is this a PIC? What kind of memory? Does it need a battery backup?

Main computer:

This box would support multiple display types simultaneously, red alphanumeric LEDs for counters, a VFD for a function menu, and maybe even a small 4x6 LCD panel for configuration/programming. It should support standard keyboard and pointer types. It would have Empeg-like functions (boot from flash) but use off-the-shelf parts. Power consumption should be as low as possible – perhaps use an inactivity timer to turn off LED/VFD display, but keep computer running overnight. It should be capable of running something like MySQL – what functions to load from what type of memory are TBD, but it would need to support some type of large-capacity storage for instructions, logging.

For all of this and for required serial, ethernet, VGA and keyboard/input requirements, it would look like I need some sort of SBC. I have looked at some of these, but can anyone recommend any one in particular? Say, some serial-centric ARM-based SBC with ethernet that would run directly from 12 volts? Do all of them use their own custom distro? Are there limitations WRT applications (like ability to run MySQL)? Some SBC outfits offer “developer kits”; is there one that is best/affordable?

This box could have 4-6 separate LED counters displaying. It seems unlikely that I could find a SBC with that many serial outputs and I wonder how to do this – can I just chain all of those LEDs together and address them with one long message?

Being much enamored of the Empeg menuing metaphor, I would expect to add a VFD menu system to control modes of operation. This would be controlled by knobs, toggle switches and maybe a 4-pole joytick. I know *nothing* about keyboard mapping on Linux machines, but is it feasible to take multiple dissimilar switch/button type and interface them through a single, custom keyboard map? Is there a place I can start to investigate this?

The Empeg's ability to store its state when powered off is something I would try to emulate – keeping configuration data like odo calibration factors, display settings etc. Most of the dedicated computers have no persistent settings thus driving the requirement to keep it powered up during breaks and long periods of inactivity.

One other general issue is the question of toolset and database interface. One of our group is a talented perl programmer and has written some nice rally calculation code (that could maybe fold into this) but I am skeptical of completing the required serial/keyboard sensor interfaces without resorting to C. In that respect, if there is any choice of PIC/SBC combinations that are best from a toolkit consistency standpoint, I'm all ears. Any other ideas or questions appreciated!!

Driver Guide:

check out this guys kits. Check out all of his kits (there's lots of them. Looks similar to what you're wanting... though the inputs are way different.

Man... you are making me want to get into rallying more and more. I never even thought about the fact that it could be a great (couple) activity with the navigator and driver! =]

Back to electronics... this looks like a fabulous idea. I wonder if you could actually use an empeg somewhere in the chain?

check out this guys kits. ..... .. though the inputs are way different.

Cool! Different, but that's the metaphor I'm aiming for. I might have to e-mail him. I would even pay someone for some of these bits so long as I learn something along the way. Being voltage driven, his light up only 1 LED, I think. For my speed up/slow down, what I want is something that you can pick up in peripheral vision (I'm even thinking quasi-HUD via reflection off a windshield film strip) where the green/red bars grow in an obvious way. Our driver display had an ahead/behind bar on the VFD, but I had to look right at it to decode what it was telling me. Better to look at the road!

I never even thought about the fact that it could be a great (couple) activity with the navigator and driver! =]

Yes, so long as one member of the couple is immune to car-sickness or has good results with Dramamine or a patch!!

Back to electronics... this looks like a fabulous idea. I wonder if you could actually use an empeg somewhere in the chain?

I gave that a good, hard, think but decided I would leave more options open if I went with a separate board/CPU/interfaces. I was also concerned about contention issues. It would not take much (especially at very high or low CASTs) to have your calculations get way off! A super-duper version of this system (even further beyond my skills!!) might even offload clocking and calcs to a 2nd CPU or ASIC.

Being voltage driven, his light up only 1 LED, I think. For my speed up/slow down, what I want is something that you can pick up in peripheral vision (I'm even thinking quasi-HUD via reflection off a windshield film strip) where the green/red bars grow in an obvious way.

There are "thermometer" chip LED drivers than can switch between "dot" style and "bar" style. Takes a reference voltage or two, voltage input and high or low to a bar/dot select pin... Some chips to check out: U1096B, LM3914N, LM3915N.
A6275/A6276 for more generic driver w/ uprocessor-interface

/Michael

I never even thought about the fact that it could be a great (couple) activity with the navigator and driver! =]


No.

Not if you want to remain a couple!

Very few marriages will survive TSD rallying, particularly if the dominant partner is competitive by nature. Some of the most vicious fighting I have ever witnessed has been during and after TSD rallies. If you haven't done it, you will not understand the pressure and tension involved. You are both unbelivably busy, the driver scrutinizing both sides of the road for subtly misleading clues, desperately trying to remain on course. The navigator is reading the instructions, painfully deciphering each one and looking for the hidden tricks and traps that rallymasters love to include. One of the best examples I ever saw was in a section where the given average speed was 20 MPH. The next instruction said: "At sign reads in part "Hygrave", divide your present average speed by one-half."

I will leave it as an excercise for the reader to discern why setting the new average speed at 10 MPH was a bad idea.

My wife and I were the exception to the rule when it came to TSD couples and rallies. We were successful at it, finishing in the top 5 in more than one national-level rally. To accomplish this, we had one absolutely inviolable rule: her word was law. I was allowed to question any decision she made one time ("Ummm, are you sure about that?") and then whatever she said was what we did. No further discussion, no argument allowed, and no recriminations if things went wrong.

"The bad news is, we're hopelessly lost. The good news is, we're making excellent time!" TSD rallying is a very intense activity, not conducive to cuddly, feel-good moments with your significant other.

tanstaafl.

Not if you want to remain a couple!

Oh, Doug, don't be scarin' Loren!

We have quite a number of couples (and some father/son teams) who seem *quite* competitive (at least they kick our butts regularly!) but who seem to get on quite well (at least in front of an audience!). Interestingly, the couple that comes to mind first mix it up -- don't always run together (and the husband's best results -- like a 17 in a 2-day BC gravel/slush rally -- were with a another, hard-core navigator). So it can be done. I see more couples yelling on sailboats. I may sometimes be a disappointment to my co-driver for not being competitive enough. I just like to drive, (Oh, and the purse money...right!)

I still think the bigger, more prevalent issue is navigator motion sickness. Unplanned stops for a good hurl are pretty common.

There are "thermometer" chip LED drivers than can switch between "dot" style and "bar" style. Takes a reference voltage or two, voltage input and high or low to a bar/dot select pin... Some chips to check out: U1096B, LM3914N, LM3915N. A6275/A6276 for more generic driver w/ uprocessor-interface

Thanks! I will look at these. interesting I just started building a a Jameco LED battery voltage monitor from a kit and it has some (smarter? dumber? completely unrelated? ) LM324Ns on there.

Now if I used something voltage driven, I'd have to build/write something to send variable voltage, wouldn't I? I was attracted by the Futaba VFD serial command set I saw when building that driver's display (including dimming), but that doesn't mean that there's anything equivalent for an LED-type display, does it? So, something in the "driver guide" display that takes serial messages and changes voltage....

I'll look at those chips! thanks!

if I used something voltage driven, I'd have to build/write something to send variable voltage, wouldn't I? I was attracted by the Futaba VFD serial command set I saw when building that driver's display (including dimming), but that doesn't mean that there's anything equivalent for an LED-type display, does it? So, something in the "driver guide" display that takes serial messages and changes voltage....

With any of the first chips you'd need a voltage signal to them.
The last ones listed with the microprocessor interface probably mean you can send a bit pattern and get whatever pattern you want (not limited to bar or dot).

There are also very generic shift registers with LED driver combined. Just shift in your bit pattern from the micro...

There seems to be fairly "smart drivers" that handle 7-segment displays (say up to 8 chars) - not too many general dotmatrix LED displays around (apart from the ad-banner style ones frequently seen in stores - might be a bit large for you), most are a number of 7 or 16 segment displays.

/Michael

Okay, i obviously have no idea how Rallys work. What i've picked up has been from sporatic watching of a few UK rallys on tv, and i know nothing of the rules/way things work. What's a good site that would explain it to me... or could one of you give me a quick rundown? I had no idea there were "clues" as to where to turn next and things like that. I thought it was straight on "30 degree right turn... now" type situations that the navigator had logged in a book or something. Hm. This is sounding better and better.

You know what's really appealing? This is gonna sound stupid... but my friend James and i always played games like Midnight Street Racer and GTA together... one of us would drive, and the other would be the navigator who would watch the onscreen map and call out upcoming turns and such. The possibility of doing this in real life has me enthralled.

I'm not sure how well Kelly would hold up to the navigator position... i hear enough guff just driving around the city about my speeds... heheh. Actually, i bet she would make a good driver, she's just as crazy as i am behind the wheel, she just can't handle not being in control of the car.

so how the hell do you get started in all this?! (sorry for the thread jacking... we can start another if you wish)

I had no idea there were "clues" as to where to turn next and things like that.

There's a difference between a "TSD Rally" like Doug was describing, and the kinds of rally races you see on TV.

The ones on TV are high powered vehicles going through "Special Stages" where they try to get from point A to B the fastest possible.

The TSD rallies are for hobbyists, and they're done on public streets at or below the speed limit. Unless you make a wrong turn and have to catch up...

so how the hell do you get started in all this?! (sorry for the thread jacking... we can start another if you wish)

Don't worry about the thread jacking. If a little bump helps somebody notice my SBC quest, that's OK!!! (I've e-mailed a company called Applied Data about their Bitsy board...

Where to get started? Well, a member of this Bay Area club came up from Berkeley for No Alibi, does the occasional BC rally IIRC, did the Winter Alcan in 2000 and is signed up to run the Winter Alcan again this coming February. Pete might be able to answer an e-mail or meet up. The West Coast Rally Assn runs both stage and "brisk" gravel TSDs and their Web page has a "getting started" page albeit with some dead links.

So, to compare:

TSD Rallies

Cost of entry $10-$2000 depending on what kind of rallying you want to do. Most folks start with the $10 stopwatch and clipboard and then gradually add equipment to suit their interest. Cost to rally say $100 to $2000 a year for a team of 2 depending on how far you want to go and how many rallies. Rallies range from "trap" and "gimmick" rallies which are more of a logic/navigation puzzle to touring rallies (many on gravel) that pose a challenge to keeping speeds under sometimes dubious conditions. Some touring rallies, like the Alcans, are something of an endurance event and can include things like ice slaloms. Other rallies (like the interesting-looking Targa Newfoundland ) combine stage *and* touring TSDs in one event.

Stage Rallies

Cost of entry: From $10,000 to > $1,000,000. Cost to operate? From, say $10,000 to $10,000,000+ per year. On the low end in the US, the sponsoring body of the so-called Club rallies is the SCCA. Used cars in North America can be found at Ben's Rally Page. You have to be prepared for the loss of the car. No insurance! Stage rallying is what you tyically see on Speed TV whether immensely expensive (WRC) or just very, very expensive (SCCA Pro Rally). Most of the folks who run in Pro rally are "in the biz" I think -- run a garage or a prep shop. Or they are living off an inheritance.

Some folks start in TSD and move on to stage rallies, but that's not to say that there is a lot of carryover. There are basic similarities: driver/navigator and a set of instructions. "Tulip" instructions used in stage rallies are much like those used in touring TSDs.

I would love to stumble across enough money for us to buy an old Mazda 323GTX or something and campaign it at about 90 percent of our driving ability in Club Rallies, but that still means about $20,000 for year one. Not in the cards. For now, we're having enough fun driving up gravel at 60-70 percent while trying not to have *that* discussion with the insurance company!

Tony: The ones on TV are high powered vehicles going through "Special Stages" where they try to get from point A to B the fastest possible.

Yes, earliest wins where in TSD early or late are equally bad... "Public Roads" is, I think, the operative term from an insurance standpoint.

Unless you make a wrong turn and have to catch up.. We bitch about missed turns or bad calcs, but it is funny how making up 2 minutes at 20 MPH over CAST over slush, ice and mud are the parts we enjoy! Until we wind up like these guys who passed us last November...

There's a great Grand Canyon rally coming up in January 2005, but I won't post the link because it may qualify as the worst Web page in the world!