Is anyone observing problems with the low battery indicator/interrupt on the Mk 1/V1.02?

One of the few remaining Mk1 owners... #00015

Only when I turn the ignition off, but leave the key in the Accessory position, then start the engine back up again.

I had that in any version (But that's how it is supposed to work).
Perhaps your electrical system needs to be looked at?

Smoker_Man
#080000449 MkII - 36Gb Blue

Luckily, in this case - no New alternator, alternator belt and battery .

What I am seeing is the unit hanging or crashing under heavy electrical loads that would normally trigger the "Batt Low" indicator.

One of the few remaining Mk1 owners... #00015

New alternator, alternator belt and battery

You are the last person on this bbs I would try and give a "Automotive electrics 101" course to -- you undoubtedly know more about the subject than I do (and I know quite a lot [he says, patting himself on the back])

But we both know that the battery icon only shows up when system voltage drops below a certain point -- I'm guessing about 11 volts. If your system voltage is going that low, that sure would imply a problem with either your alternator, your voltage regulator (no doubt integrated with the alternator if your car is less than about 25 years old) or your belt.

By any chance did this problem arise right after you installed the new alternator? Naaah, you'd have thought of that approach already.

The only time I have ever seen that icon is at an IASCA competition where I ran the stereo for a long time without running the engine. When the battery icon showed up on the empeg, my battery was already so flat that I had to use jumper cables to get the engine restarted.

Only thing I can think of... it must be some sort of operator error.

tanstaafl.


"There Ain't No Such Thing As A Free Lunch"

Actually.. I am also seeing this problem on a brand new 2001 PT Cruiser install. These are the steps I have to do to reproduce it.

1. Turn my key 2 clicks to power everything but not start the car.
2. Turn on empeg and play music.
3. Start car.
4. Empeg shuts off for a second but when it comes back on it still plays music but blinks the battery icon for about 5 seconds.

Is this a problem? Is this normal?

Thanks,

Cruz Ths

That is quite normal - when you start the car your starter motor
pulls a lot of current out of the battery, dragging down the voltage.

Depending on how much the battery voltage drops you might or might
not get the brief shutdown, while you still might get the battery symbol.

I don't recall the exact voltage levels where the indicator triggers and
where the display/output is suspended, but I'm pretty sure they've been
mentioned on the board - maybe in the FAQ?

/Michael

I'm guessing about 11 volts

Mike said it was 10. Given that a healthy lead-acid battery driven by an alternator should be giving a total voltage of around 14 while the engine is running, 10V does sound like a big drop. However...

If your system voltage is going that low, that sure would imply a problem

Ahhh - but this is a "Prince of Darkness" special - a Mini. These things have ridiculously small batteries, so even when new, drops like this happen regularly. Imagine:

- cold day, cold start (-10 C, no-where near as bad as your neck of the woods!)
- lights on
- rear window element on
- blower on

You then drive to the first set of traffic lights on Red, foot on the brakes and the empeg throws a wobbly. I'm used to this happening now, and the expected behaviour is for the interrupt handler to kick in and do the screen blank routine. However, since 1.02 hit the box, it now:

- stutters
- the graphics lock
- the music stops

and then BANG! After about 5 seconds it re-boots. Definitely odd behaviour in my book!

One of the few remaining Mk1 owners... #00015

I'm no expert, Rob, but that sounds like the hard disk doesn't like the drop in voltage.

Have you tried wiring one of those capacitor/diode assemblies like I did for my Mark1? It took care of my reboot problems on my Mark1.

___________
Tony Fabris

I get the same as CruzThs. Its not a problem for me, it just makes me feel dodgy when the battery icon comes on.

As for rebooting, my empeg normaly reboots when i turn the engine on, or off then on, depending on how quickly the engine turns over. If it goes "chchchchchchchchchchvroooom" it will reboot, if it goes "chchchvroom" it wont. However, ive not done any scientific tests, so its probably just random. either way, i dont care, it still works, and it appears to do no damage..

Hmmm... I would normally just agree - it sounds as if the player couldn't get any response from a disk I/O request, or from cache.

The problem is with this is that before 1.02, the display would blank and then it would come back with the battery low icon. With 1.02 it changed and it just kinda goes "KABLOOEY!!", which is pretty uncivilised. It's the change in the low battery behaviour that made me ask if anyone else was seeing this.

One of the few remaining Mk1 owners... #00015

Did you make any other changes to the configuration around the time of 1.02? For example, installing the developer image instead of the consumer image (less cache)? Or installing displayserver (even less cache)?

___________
Tony Fabris

Nope, always Consumer, whatever version.

One of the few remaining Mk1 owners... #00015

This is normal; the Mk2 will continue running down to an input power of about 6v. As the power input dips below 10.16v, the empeg assumes it's losing power and saves the current state in flash, turning the display off (which also turns the amps off).

It them sets a timer; if this timeout is reached, power obviously hasn't gone away and it turns the display back on and continues. The battery symbol indicates that the empeg is currently ignoring any more power fluctuations - we added this as one mk1 customer had big amps and a weak battery leading to this situation:

empeg turns on amps. Power drops below 10v, display & amps off.
Power recovers, empeg turns amps back on. Repeat.

Hugo

As the power input dips below 10.16v...

Is that value in the software someplace? Perhaps it could be configurable for extreme tech-heads who know that it's normal for their car to drop to 9.78 volts sometimes. Maybe a config.ini entry?

They could adjust the cutoff voltage to reduce the number of reboots, at the expense of the unit's ability to reliably state-save on a power yank.

___________
Tony Fabris

Sorry, nothing that hi-tech. It's a potential divider (ie, 2 resistors).

If the unit does a *complete* reboot, then this means the voltage dropped so low that the PSU could not maintain a constant 3.3v supply to the CPU/RAM - and hence the CPU reset/power monitor chip forced a reboot. No amount of tweaking the threshold would have helped in this case.

Hugo

Actually, no publicly released version actually works very well in this regard. I only realised that the behaviour was wrong when it started happening in my car and the battery symbol went away when I didn't expect it to.

Here's what happens at the moment in all publicly released versions of the software:

The power drops below the threshold voltage triggering the state save and turning the display off.

A few seconds later the display is turned back on but the powerfail indicator comes on. A timer routine is scheduled to run a few seconds later.

When the timer routine runs it checks whether there have been any further drops below the threshold in that time. If there haven't then the powerfail indicator goes out, otherwise the timer routine is scheduled for a few seconds time and the indicator remains visible.

This works well for momentary glitches such as starting the engine and erratic power sources but in the persistent low voltage case it does the "wrong thing"(tm). It is possible for the player to be unable to save state when power is lost (because the voltage is already below the threshold) but there is no indication of this on the display to warn the user.

Here's what our development source does (for both v1 and v1.1):

The power drops below the threshold voltage triggering the state save and turning the display off.

A few seconds later the display is turned back on but the powerfail indicator comes on. A timer routine is scheduled to run a few seconds later. (No change so far).

When the timer routine runs it checks whether there have been any further drops below the threshold in that time and whether the voltage is currently above the threshold. If there haven't and it is then the powerfail indicator goes out, otherwise the timer routine is scheduled for a few seconds time.

This is much better. If state save is not possible due to low voltage or an erratic power line then the indicator will be displayed.

I hope that makes the situation clearer. If anyone is suffering from problems with not remembering state or powerfail then email bugs@empeg.com and I'll try and send you this update to try so you can at least see what is going on.



--
Mike Crowe
I may not be speaking on behalf of empeg above :-)

I just noticed this happening in my new car, but it never happened in the '93 Civic. When i shut the car off (usually when i'm waiting for my carpool guy to get his ass downstairs) then keep listening to the empeg... then restart the car... I get a big thump in the speakers (sorta to be expected i think.... still figuring that out)...but the relevant thing is that it returns to the OurEmEss LR visual everytime now matter what visual i had it on before. I'm not sure if this is relevant to what you are mentioning above or not.... ideas?


|| loren.cox || 080000446 ||

A correct car installation shouldn't thump your speakers. I can rip and jam my empeg in and out of my Carrera with wild abandon. A friend of mine has a thumping installation (more like a gunshot!). After swapping empegs and finding his car thumped with either, we took an empeg to the lab bench with a spare docking sled I happened to have laying around. We hooked up the RCAs to an amplifier which did not shut down in response to the empeg's remote line and found that as long as the yellow "Permanent power input" line was hot, you could flicker the orange "Ignition sense input" recklessly without a thump. If you connect the AC adapter or fiddle with the yellow wire, it thumps mightily. Interestingly, the yellow input is not necessary to run the empeg, but if you don't use it, you will get a thump when you light up the orange line. Hope this helps. Also check out Hugo's earlier posts on thresholds. Very interesting!

-jim

On the newer (mk2a, rio branded) units, the yellow wire *is* required as the psu input circuitry has changed. Previously, due to a diode in the circuit, powering by the orange wire only would run the unit (not ideal!)

Hugo