I am reposting an email I sent to SSOLIE and Lhaze because it might be of interest to you people whos A1 eats batteries.

Note at 5uA the battery should last between three and five years

Dear Lyle,
Steven forwarded your email to me thinking I might be able to help you. Today my office manager handed me this email during a lull at work first one in a very long long time.
So I popped my A1 on the bench as luck would have it also happened to be at work today ( I was using it to re-setup OS4 on my classic which had literally melted )
I hooked the battery port up to my calibrated scientific bench supply set at 3.2 volts and proceed to play.
Disclaimer I for whatever reason have been lucky as my batteries last for years.
A1XE 800 750FX one 512MB DIMM, Onboard audio and 9250 PCI 256MB Uboot 1.12 Oct 2007

Off 4.7 uA
On running OS4 4.5uA this was consistent in all tests.
but I noticed during POST and loading of OS4.1 the current draw varied from a low of 4.4 to a high of 5.3 streaming up and down rapidly
Then settling at 4.5uA running OS4 no matter what I did.
Booting OS4.0 Final resulted in a more wild swing with current draw going from 4.4 to 8.9uA
once OS4 booted the current would stabilize at 4.5 and stay there copying files streaming music USB,LAN made no difference.

unplugging the A1 would result in a quick surge of current spiking at 1253 uA before settling at 4.4 ~ 4.7 uA the final stabilized voltage would vary from unplug to unplug.
replugging my A1 would sometimes resulted in a quick current spike of between 8 and 800 uA before settling down at 4.7uA

Now I started to play with a variations of PCI cards I will explain my reasoning in a minute.
The startup current draw would vary depending on the mix of PCI card from 4.4 to 5.3uA. (Just booting to uboot not booting OS4 )

Now I will explain my reason for trying a number of PCI card combos.
A number of years ago when the uA1s were first hitting the street, I stuck a Cmedia sound card in my A1 the same as the chip in the micro and the current draw on the battery was so great the voltage from the battery would collapse and not only would the machine not boot but it would scramble my Uboot settings
This was repeatable and each time I stuck the card in my machine and tried to turn it on the same thing would happen. I blacklisted the Cmedia card and instead sold SB live and AU801 cards.

Today imagine my surprise when I stuck that very same Sound card into my A1 and it booted just fine with no abnormality in current draw on the battery socket.
the only difference is then I used a 9800SE card in my A1 and today I have a 9250.
The other difference is the Uboot version and I am suspecting that now because after my testings it is looking like a back door current draw.
The proof of this on how current varies as Uboot and then OS4 initializes the hardware.
Even the slight difference in the OS4.1 and OS4.0 final kickstart layout resultes in a 3.6uA difference in boot current tells me its not a simple hardware ####up but a combo of software and straping of the Via.
What is happening is that current is leaking backwards through the VIA 686B as gates are being turned on and off.
This makes allot of sense because the Via AC97 audio codec and the RTC gates are multiplexed internally. Audio was not initialized properly in Uboot and that is why the AC97 codec was removed from the later A1boards and the Cmedia was added to the micro because Hyperion could not figure out how to properly initialize the 686b in uBoot to make noise. It also makes sense as to why the current stabilizes as soon as OS4 starts and sound codec is initialized.
People without the codec or who use different sound cards might be experiencing abnormal current draw on their batteries. I also suspect different uboot versions might come into to play

Lyle if you want I can send you that unofficial uboot and see if it helps you with your micro eating batteries.
measure current before and after the switch. Since I no longer are in possession of a micro I can't test this out.

Edit I also did a quick test of the A1 running linux battery current varied up and down and stayed at 5.3 after booting and hard drive or CDROM activity caused a swing in current. Note this is an older version that required a 7000 card and does not support the internal sound codec.

Kgrach

Last edited by kgrach on 30-Sep-2008 at 05:58 AM.

@kgrach

Quote:

Audio was not initialized properly in Uboot and that is why the AC97 codec was removed from the later A1boards and the Cmedia was added to the micro because Hyperion could not figure out how to properly initialize the 686b in uBoot to make noise.

Actually, I was told by MAI that the codec wouldn't work. I never even tried to do anything with it. Unfortunately, the VIA handbook didn't help at all because they didn't list any initialization sequences.

The latest (yet unreleased) U-Boot (1.3.4 which I am currently working on) contains a wakeup sequence for the VIA that might or might not cure some of the battery problems. If you want to test it, contact me in EMail. It might be interesting to see whether this helps or not.

_________________
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@kgrach
Thanks for all that work.
John Paul

@kgrach

My intent is to create a battery replacement that will provide a regulated 3.3 volts. I believe this will improve the stability of many A1 systems.

I had hoped to have a working device before announcing it to the public, but that opportunity seems to have passed.

To do this right, I need to see a set of schematic drawings for the MAI/Teron boards. Of interest is the battery circuit and everything connected to it. I need to make sure this new battery replacement won't cause more problems than it solves.

If anyone has prints, please let me know, by forum, PM, or E-mail.

Thanks,
Lyle

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question=(2b||!(2b))

@kgrach

Then, is it safe to install the AC97 chip/codec in a A1 without it? I bought one some months ago, but I have not installed it yet (no time nor the means to do it)...

Saluditos,

Ferrán.

_________________
Amiga user since 1988
AOS4 Betatester
Member of ATO Spain
A1 Cfg
OS4 SCR
A1200

@kgrach

I am uaing on board sound, with a 9200se card, and have only had to replace my battery once, since I got my A1XE800 G3. Does that fit in with your scenario?

Last edited by Swoop on 30-Sep-2008 at 04:23 PM.

_________________
Peter Swallow.
A1XEG3-800 [IBM 750FX PowerPC], running OS4.1FE, using ac97 onboard sound.

"There are 10 types of people in the world: those who understand binary, and those who don't."

@lylehaze

Sorry Lyle the battery is hooked directly to the VIA 686B so any problems is related to the SB
there is nothing to check out. The only thing I could not figure out is if the low battery is tied to the 3.3 volt line with a 10 k resistor or is tied to the battery.

I didn't mean to cut you out or anything If this can't be fixed via software. You still can make something. But beware the style of battery holders vary from model and version of the boards.

I would contact Rogue and see if the beta Firmware fixes your micro.

kgrach

@kgrach

No problems dude.
I am sure there's more going on here than even your first posting revealed.

Everything you posted was great, but there are stability problems even after bootup. They are minimized with a fresh battery, but this is still not ideal.

I remember when I first realized all this, I thought it was _really useful_ information, but I was told that programmers can't fix hardware problems, and I should just change my battery and shut up. I believe that understanding why the hardware fails can help a programmer to write code that will run more reliably on that hardware. But then, that's just my opinion.

I'll do anything I can to support improving the software end of things, but I believe I'll also design a new battery pack. What I find interesting is that my Micro is on 24/7. It is shut off only for occasional drive changes. My battery SHOULD have no effect on the stability of the system, but it does, big time.

The nice thing is that you've given me a great profile of the expected load on the battery replacement. Now off to design a solid 3.3v backup system. Probably self-charging from a spare drive power connector.

These things have different battery clips? I wonder why the change?
I'll have to design one that will fit my own micro, and then we'll see how it works on the others. But if the "insert" is the size and shape of a CR2032, the only problem might be where the 2 wires come off of it. That shouldn't be too tough to work out.

I'd still love to see prints to make sure that I won't feed power back into something else.. If anyone has diagrams, please let me know!

Thanks,
Lyle

_________________
question=(2b||!(2b))

@kgrach
Thanks for doing the testing Kurt.
This could prove useful for current UBoot changes as well.

My SAM440ep has not nibbled any batteries so far.

_________________
ExecSG Team Lead

@ssolie

Could you send it here for further testing?



Lyle

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question=(2b||!(2b))

@lylehaze

One thing that I have noticed with my MicroA1, I don’t know if any one else has noticed
But when I turn My Broadband router on, the Connection light is lit even though the MicroA1 isn’t turned on so its drawing power from somewhere on the Micro. ( note this doesn’t happen with the laptop plugged into the same router its connection light only lights when its powered on) If I use the Micro and when switched off the Connection light then goes out. Its not a problem but like I said its getting power from somewhere and no its not the Router as its happened on another two routers ( different makes) maybe something else to look for?

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@ajs

Quote:

But when I turn My Broadband router on, the Connection light is lit even though the MicroA1 isn't turned on

Your A1 is turned on at the powersupply if not the front switch. (I would guess)

This happens for me too, I leave my PSU switch on 24/7 so that light is always on (unless i quit linux whwn it switches it off on shutdown).

So far I haven't drained a battery. Although I do have problems booting if I switch the rear power supply button off. Which might mean it's on it's way out. Fortunatly I just bought apack of two as the battery in my new Behringer V-AMp Pro was dead on arrival (couldn't be bother to ship back to germany for the sake of £1.50).

_________________
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@kgrach

VBAT is connected to the supply of the NVRAM over a BAT54C double-diode.
According to it's datasheet the W24258 should take 2 µA in standby.

Then it supplies a NC7SZ66 which is a single switch.
According to it's datasheet this one draws 10 µA at max.

And then it is connected to the VIA VBAT pin which supplies the RTC.

If have a revision 1.71 datasheet of the VIA686B from June 2000.
It's here for example:
http://www.datasheetarchive.com/datasheets/Datasheet-01/DSA0017453.pdf

There is close to no information in this however regarding design considerations or how much power is supposedly drawn thru VBAT to supply the RTC.
VBAT is hardly mentioned at all.
So this is of no help.

BATLOW of the VIA is not tied to VBAT over a 10k resistor but to some 3V supply.
And according to it's datasheet it is to be tied to 3,3V if not used.

@broadblues

Quote:

broadblues wrote: @ajs Quote: But when I turn My Broadband router on, the Connection light is lit even though the MicroA1 isn't turned on Your A1 is turned on at the powersupply if not the front switch. (I would guess) This happens for me too, I leave my PSU switch on 24/7 so that light is always on (unless i quit linux whwn it switches it off on shutdown). So far I haven't drained a battery. Although I do have problems booting if I switch the rear power supply button off. Which might mean it's on it's way out. Fortunatly I just bought apack of two as the battery in my new Behringer V-AMp Pro was dead on arrival (couldn't be bother to ship back to germany for the sake of £1.50).

Hi Andy, well I've only replaced one battery since getting the Micro a long time ago, but its still strange that the Router Connection light lights up
OK the Micro is plugged into the Mains but it isn't power on and the laptop is in the same Gang socket so why doesn't the light ,light up for that until its powered up
like I said its not a problem just thought these people looking for " THE DRAIN" might like another option
Regards
Andy. .......................oh is that an Echo?

_________________
Everything is proceeding as I have foreseen

Some people are like slinkies. Not really good for anything but they bring a smile to your face when pushed down the stairs.

Hi @kgrach

What is happening is that current is leaking backwards through the VIA 686B as gates are being turned on and off.

Thanks for confirming the missing 'blocking diodes'. I had always believed this to be problem with some of the A1s. This not a problem with the A1-XE models.

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@Snuffy

>Thanks for confirming the missing 'blocking diodes'. I had always believed this to be >problem with some of the A1s. This not a problem with the A1-XE models

What missing blocking-diodes?
This is *inside* the VIA686B.

@ajs

ATX power supplies always supply a 5V standby voltage that keeps the network card online, among aother things, so it can wake-on-LAN and run IPMI. Only way to switch of an ATX power supply completely is to pull the plug or switch of the physical switch at the back on the actual PSU, if it has one.

This is normal behaviour of all (modern) desktop and server computers. Laptops on the other hand are not designed to be able to wake up on LAN signals or any other remote operations while switched off, so it doesn't have this feature. Also, it wants to conserve power as much as possible so it won't have anything on unless it has to.

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@Ferry

Yea, I ask the same!
I also plan to solder the AC97 chip on my A1-XE tomorrow actually.
Will I run into any trouble with the battery? I have never had problems with it before.

_________________
- Don't get fooled by my avatar, I'm not like that (anymore, mostly... maybe only sometimes)
> Amiga Classic and OS4 developer for OnyxSoft.

@Deniil715

actually the battery drain goes down when the AC97 is initialized and stays stable.
I will try to borrow a micro and see how it reacts.

problem is there was several HW revisions of the micro sold.

kgrach

@Deniil715

Thank you for the explanation,
Ok can you answer this why when I've used the MicroA1 and then turned it off by it's power switch ( not the PSU switch and still on at the mains) the Router Light goes out? Hmm



( no you don't have too answer )

_________________
Everything is proceeding as I have foreseen

Some people are like slinkies. Not really good for anything but they bring a smile to your face when pushed down the stairs.