The most useless accessory in my car is now even more useless

[Shoeless]

My car has this date display which I think is the most completely useless accessory possible. It's not part of the clock - the clock is part of the radio display. This date display is a separate LED display built into the plastic thing on the ceiling that the rear-view mirror hangs down from, which also has the sunroof controls and the compartment for my sunglasses. In fact, if it weren't for me looking up to get my sunglasses, I'd probably forget the date thing was even there.

It doesn't even display the year. Just the month and the day. Hey, if you're going to put a date display in the car, you might as well go all out, right?

Apparently leap day has thrown my date display for a loop, because my car still thinks it's February. Yesterday the date display said FEB 30. Today it says FEB 31. So now this useless accessory is even more useless because it's WRONG!

Any guesses when it will eventually roll over to March? My guess is that it will be tomorrow (on the assumption that a max of 31 days is programmed in). But part of me hopes to see it go all the way up to 99.

[Lancia]

What kind of car (make, model, year) is it?

[guizot]

Does your car have a CB radio? I've heard that those were popular, too, at one time.

[davidm]

There's no way to adjust it?

[Frank]

Originally Posted by Shoeless

In fact, if it weren't for me looking up to get my sunglasses, I'd probably forget the date thing was even there.

I don't have a date thing in my car where my sunglasses holder is. Of course, my sunglasses holder doesn't hold my prescription sunglasses. I'd call that pretty useless.

Not to mention the cigarette lighter outlet that no longer comes with a cigarette lighter.

[Acsenray]

Feb. 31. I'm giggling.

[Shoeless]

Originally Posted by Lancia

What kind of car (make, model, year) is it?

It's a 2003 Hyundai Santa Fe.

Originally Posted by davidm

There's no way to adjust it?

Yeah, there is. I just want to see where it goes on it's own.

[beowulff]

I'm pretty sure it's a clock, also.
My wife has a 2002 Santa Fe, and that's where her clock is.

[Shoeless]

Today it says FEB 32, so this could go on for a while.

[johnpost]

tell us what happens after FEB 39.

[davidm]

Maybe it will hit Feb 99 then, the next day when it tries to roll over, all the electronics will lock up and the car won't start. Either that or the car will explode.

[Michael63129]

Originally Posted by Shoeless

It's a 2003 Hyundai Santa Fe.

Yeah, there is. I just want to see where it goes on it's own.

Did you have the car in 2008, and if so, did it work correctly then? If it did, it is weird that it is screwing up in 2012 but not in 2008, which should be the same since no year is involved. Or maybe it is because it is 2012... Seriously, I think it is some software bug where the programmer had it change month when the day reached 28 in February (i.e. Feb 28 becomes March 1, but for leap years it goes to Feb 29... then the logic fails because it is like "if(day == 28){month++;}"; this expression fails for day = 29 (to avoid this, logic for leap years can be added; check for 28 for non-leap years and 29 for leap years and change it to "greater than or equal"). This assumes that the year is indeed stored somewhere but not displayed. Anyway, it will be interesting to see what happens when it reaches 99, probably just rollover (I really doubt the car will fail, what would be that dependent on the date; I once found an old computer where it thought 20xx was 19xx yet it worked just fine).

[DMark]

That's what you get when you buy timepieces from Mayans.

[TBG]

Originally Posted by Frank

Not to mention the cigarette lighter outlet that no longer comes with a cigarette lighter.

That's not useless at all. They're there to plug things into. I don't think they even call it a cigarette lighter anymore, it's a "utility port" or something like that.

I don't use one very often, but I use it more than I ever did to light a cigarette (never).

[Reply]

Originally Posted by TBG

That's not useless at all. They're there to plug things into. I don't think they even call it a cigarette lighter anymore, it's a "utility port" or something like that.

I don't use one very often, but I use it more than I ever did to light a cigarette (never).

It's a TomTom conspiracy to put Marlboro out of business, I tell ya.

[Mangetout]

Originally Posted by Shoeless

Today it says FEB 32, so this could go on for a while.

Please can we see a picture? Pleeeeeeeease?

[don't ask]

Originally Posted by Frank

Not to mention the cigarette lighter outlet that no longer comes with a cigarette lighter.

Mine has one of those and I only discovered it the other day. It is in front of the gear shift alongside a little recess that holds my security gate tags but has a spring loaded flip lid. I guess the recess is designed to hold a packet of cigarettes but the car has no ashtray?

[postcards]

Originally Posted by don't ask

...but the car has no ashtray?

If you check the options list for many cars, you'll probably find a 'lighter/ashtray' package listed. With Volvo, I think the ashtray is an insert for the cupholder.

Hey, Shoeless, what's the update on today's date? Is it the 33rd?

[casdave]

This thread has the potential to be a very long one

[Shoeless]

Originally Posted by Michael63129

Did you have the car in 2008, and if so, did it work correctly then?

It didn't work in 2008 (or 2004) but I just reset it instead of waiting to see how far it would go. This time around I decided to have some fun with it. I doubt I'll still have this vehicle 4 years from now!

Originally Posted by postcards

Hey, Shoeless, what's the update on today's date? Is it the 33rd?

Yep.

[Fear Itself]

From the manual:

How to adjust the date.

1. Whenever "M" button is pushed, the "YEAR","MONTH" and "DAY" each blinks in order.
2. Adjust the date by pushing " (UP)", "(DOWN)" button when the year/month/dayblinks.
3. After adjusting the date, push "M" button once more and the adjustment is completed.

Don't know how this squares with the actual controls on your car.

[zweisamkeit]

So? He's said that he has corrected it before; it's just damn funny (especially when it rolled right past 31).

[davidm]

Sounds like a bounds error of some kind. The leap year code must erroneously bypass the constraints entirely rather than just allowing an extra day.

The code probably tells it to rollover on midnight 2/28 but not on leap year, but then doesn't have any constraint beyond that.

[Senegoid]

Originally Posted by davidm

Maybe it will hit Feb 99 then, the next day when it tries to roll over, all the electronics will lock up and the car won't start. Either that or the car will explode.

I'll put my money on it running up to Feb 99 and then rolling over to Feb 00.

[BigT]

I'm subscribing to this thread. I know I don't have to post to do that, but I wanted to announce it. I hardly ever subscribe to any threads, but this one is interesting and likely won't be finished for a while.

[Shoeless]

FEB 40 and counting...

[MC$E]

Wow, and I thought my Dodge Durango that would go from 3:59 to 3:60, then about 3 seconds later to 4:00 was cool.

[Mangetout]

I reckon it's got some mis-ordered or mis-nested conditional checks in the code - which probably means it has no way to get out of February in a leap year. That means one of a few things could happen:

It might count up to 99, then click back to Feb 01 (maybe 00) - and continue doing this until the end of the year.

If the date number is a single byte value, it might continue incrementing it until it gets to Feb 255, then back to Feb 00 or Feb 01 - except that it probably can't express anything beyond Feb 99 on the display, so it might display nonsense, or nothing, or some kind of truncation (i.e. displaying 01 to 09 instead of 101 to 109, or displaying 10 for the whole of that range)

I'd be really interested to hear from someone with experience of programming devices like this - would I be right in assuming it's got a microcontroller in there? Is it possible to actually write a program with unhandled exceptions that crashes one of these devices, or will it keep on churning through instructions no matter what?

[Antigen]

Originally Posted by Shoeless

Apparently leap day has thrown my date display for a loop, because my car still thinks it's February. Yesterday the date display said FEB 30. Today it says FEB 31. So now this useless accessory is even more useless because it's WRONG!

Has it been going through to 31 on months that have only 30 days?

[davidm]

Originally Posted by Senegoid

I'll put my money on it running up to Feb 99 and then rolling over to Feb 00.

At that point it will tear a hole in the time/space continuum and nobody can say what happens then.

Just keep it below 88 MPH!

[aerodave]

You car is just trying to give Black History Month the support it deserves.

"Shortest month of the year? Fuck that!"

[kenobi 65]

It's still February...for extremely large values of February.

[billfish678]

If they were being really efficient with their bits it might roll over at Feb 64 (63 even?). Though given it didn't roll over at 32 means it probably won't at 64.

Reminds me of one of my lazy habits. I put stuff in the microwave and almost allways put in something for like 66 seconds, 99 seconds, 2:22, 3:33, 9:99 minutes and so on. So my microwave allows seconds that should not be allowed to exist under human laws.

[Shoeless]

Update: It's FEB 61, and that's no joke.

[robardin]

Originally Posted by Shoeless

Update: It's FEB 61, and that's no joke.

So May 8th is when it's gonna presumably read "Feb 99", yeah? That means May 9th is the day to really watch for on this thread... (Sets Google Calendar reminder)

[OttoDaFe]

I wonder — is there any apocalyptic sect/myth/legend that sets 5/10/2012 as the date for The End™? If so, the clock in the Shoelessmobile may be trying to tell us something.

[billfish678]

I think Feb 99 is when this happens, except to the OP's car instead (link safe for work but kinda loud).

http://www.youtube.com/watch?v=Nck5Qcwq7fU

Hint to OP. Pack some extra food and water.

[robardin]

By my back of the napkin calculations, today is Feb 99, 2012:

29 days in Feb
31 days in Mar (to Feb 60, as it were)
30 days in April (to Feb 90, as it were)

so May 9th = Feb 99.

So how's it looking on that 2003 Hyundai Santa Fe today, Shoeless? And needless to say, please do tell us what it shows tomorrow morning!!

[Rick]

So the world ends tomorrow?

[Shoeless]

It does indeed say FEB 99 today. I checked this morning before I left for work. I haven't actually driven the car since the weekend because the weather has been so nice I've been taking the bike to work. I'll check it again tomorrow and let y'all know what happens.

[davidm]

Just make sure that no one is inside (or even near) that car at midnight!

Time warps can be nasty things.

[Asimovian]

"...and Shoeless was never heard from again."

[Shoeless]

I woke up to a bright flash of light and a dull roaring noise, and went outside to see a swirling vortex in the driveway where my car used to be...




Seriously though...

Just for reference, here's a photo of FEB 99 from yesterday.

And here's what it looks like today. Not at all what I was expecting.

SPOILER:

It looks like it is trying it's best to go to 100. FEB ⁰0.

[Sudden Kestrel]

Originally Posted by Shoeless

And here's what it looks like today. Not at all what I was expecting.

SPOILER:

It looks like it is trying it's best to go to 100. FEB ⁰0.

Har! That's priceless. You need to send Hyundai a link to this thread.

[MacTech]

Hmm, possible explanations…

Your Hyundai was built in an alternate reality, where February never ends
Or it was made in the South Korea on Mondas, Earth's twin planet
Maybe it was made on Bizzaro Earth, in Bizzaro South Korea

Or perhaps it's just a bug in the clock/calender software, but that's the hardest one to believe, gotta be one of the other three…

[hajario]

I had something similar happen on my non-Y2K compliant version of Quicken back in the day. Every thing worked fine except they put a weird symbol where the first zero of the year should have been.

[Rick]

Originally Posted by Sudden Kestrel

Har! That's priceless. You need to send Hyundai a link to this thread.

I already have.

[Lionne]

So tomorrow it will read FEB half-zero 1? Please keep us updated!

[davidm]

I can make an educated guess as to what's happening with the display.

I'm guessing that the two devices that display the two digits of the date each take an 8 bit value as input and use a lookup table to determine what segments to light. Input values of 1 to 9 would be displayed accordingly. Higher values may be used for other characters that a designer might want to display. In this case 10 is used for a degree symbol. At least I think what's displaying is a degree symbol. It makes sense since displays like this are sometimes used to show temperatures.

I'm going to predict that tomorrow, the least significant digit (the one on our right) will be one and that the other one will remain as it is. The leftmost "digit" will then remain as it is while the rightmost digit will continue incrementing each day until it hits 9. Then it will change to 0 and the leftmost will change to some other character or maybe go completely blank.

You're fortunate the car didn't travel to 1955 when it displayed 88.

[kanicbird]

At least it's shown itself useful as entertainment