Last known issue fixed


Great to hear that all the known bugs have been fixed. Can't wait for the prototypes to start going out!! :D
 
Time for some analog-world testing ?
Were the wifi, bluetooth, LTE performance tested to validate no problem with the radios ?
 
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Are you sure letting the voltage drop to 3.7 V is safe? or could we end up melting some USB cables with that? (dunno anything about power, but I've melted some ATX PSU cables by drawing too much..)

Also, what if I have USB cables that deliver less than 3.7 V normally? (they're very long...) :|

My experience with bottom-quality USB cables is that they tend to fail safely by just not working. Either the wire melts at a thin spot, or they break due to mechanical stress.

I managed to end up once with a pack of 40 or so USB cables that came free with some off-brand arduino boards. After attempting to use them on a device drawing 300mA, I got a 20% failure rate, but no fires or melty messes.

Either way, the answer is to buy some decent-quality (and appropriately rated) cables.
 
Is there an alternative option to power off the screen and/or underclock the CPU during boot so it can start with merely standard USB 500mA power? (preferably auto-detecting what it has power available to do..)

That won't even be enough for the OMAP5 :)

Are you sure letting the voltage drop to 3.7 V is safe? or could we end up melting some USB cables with that? (dunno anything about power, but I've melted some ATX PSU cables by drawing too much..)

Yes, every other modern device does that as well - otherwise you wouldn't be able to charge or use it properly.

Also, what if I have USB cables that deliver less than 3.7 V normally? (they're very long...) :|

Then the Pyra will crash - unless you have a battery in there.
 
It picks one, the charger chip only has one AC input.

AC ? Does it mean Alternate Current ? I thought USB was DC.

Well, it alternates between 3.7 and 4.x V depending on the cable, it seems :p

Congratulations for finding the solution. .

I'm also lost regarding the tests with 4GB RAM. Any progress there ?
 
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It's a common practice to refer to the external power port of an electronic device as an AC input even if the device itself takes DC.
The idea being that it's ultimately fed from an external power adapter that does get it's power from an AC wall socket.

-Neelix
 
Either way, the answer is to buy some decent-quality (and appropriately rated) cables.
How to identify these? (Also, any tips on finding one that will break before my N900's USB port if it gets snagged? Lost one N900 this way already...)

That won't even be enough for the OMAP5 :)
Even underclocked?? Every phone can boot off a dead battery with standard USB power I think... :/
 
Even underclocked?? Every phone can boot off a dead battery with standard USB power I think... :/

Many Phones are not even able to boot/run from any external source without the battery. So with an empty battery you often have to wait a while before booting, until it is charged a bit.

The number of Phones that are able to run from a 500mA USB without a battery should be even smaller.
(edit: i meant: smaller than the number of phones that can boot from external sources without battery in general)
 
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This is wonderful! So, are there any negatives to lowering the minimum down to 3.7V? Why isn't it always set that way?

Thanks for all the work!
 
This is wonderful! So, are there any negatives to lowering the minimum down to 3.7V? Why isn't it always set that way?
There is a negative. A weak cable burns significantly more energy if we let this voltage go down to 3.7V instead of 4.4V (Watt = Volt * Volt / Ohm). So this is likely a limitation specified somewhere in the USB standards and the chip tries to do its best to fulfill them by default (after hardware power on reset). Until we override something by software.
Anyways all this is only a problem if someone wants to operate a Pyra without battery and from wall charger only. This is more a lab environment setup than the standard operation mode with battery.
Booting from dead battery is a different and unrelated story. There is a special charging mode where the charger does only charge and not supply the OMAP until the battery has been significantly charged. Then, there is collected enough energy in the battery to boot.
 
[QUOTE="Askarus, post: 1394244, member: 59762"
Getting the remaining tweaks for about a year now...[/QUOTE]
tweaks: contraction originating from: two weeks, see also: two months
Hey Askarus... when are you going to add your feet and head to your avatar? It's been a year now... havent been able to look you in the eyes. And don't be ashamed for wearing sandals. :p


And for one years, the Evil Dragon collected many materials like metals and rare earths. Using his wings, he visited many far away kingdoms and consulted with their seers and wise men.
The wise men from the south taught him about a material stronger than mithrill. The device [chest] would be protected by it . The wise men from the east created the smallest components to adorn the innards.
The wise man from the north drew many small lines on the three tablets the device would have. And the wise man from the [Middle?] west told him to keep the chanting connection, and to not do how others had done.
He made haste, because the device was to be produced before the great war started. The great war was against the golem, which looked like the device, but were not the device.

Finally, after the one year, there were two months, but the last three days of that second month were special.

From the book of the Dragon, chapter 3:2
 
How to identify these?
They'll have a little stylized 'A' on them
Seriously, Anker is the best product for your money, in my opinion. They cost a bit more but you can save money by buying multi-packs off amazon. Got a 6 pack of various lengths for $12 and have no regrets about it. They charge better than any other cable I've found, which from reading this thread would probably be because other cables have a higher resistance where these are very low resistance. Such good cables.
 
Thanks for the update! Since tiler is apparently fixed now, I'm really looking forward to the promised video. Although getting prototypes out to developers will hopefully result in some videos too, which I'm fairly confident would push up past 1000 preorders quite quickly :) Please keep us informed about how many prototypes have been sent out - I was under a misapprehension that some prototype units had been sent out some time ago, so clarity on this would be appreciated.

Very exciting news though, thanks!
 
They'll have a little stylized 'A' on them
Seriously, Anker is the best product for your money, in my opinion.
I have personally had good luck with cables from Volutz. The people that got the rest of the cables from the bundle I purchased don't seem as pleased with them, although they also have a tendency to murder any cable they encounter. I have only heard good things about Anker, so I will recommend those as replacements for them.
 
There is a negative. A weak cable burns significantly more energy if we let this voltage go down to 3.7V instead of 4.4V (Watt = Volt * Volt / Ohm). So this is likely a limitation specified somewhere in the USB standards and the chip tries to do its best to fulfill them by default (after hardware power on reset). Until we override something by software.
Anyways all this is only a problem if someone wants to operate a Pyra without battery and from wall charger only. This is more a lab environment setup than the standard operation mode with battery.
Booting from dead battery is a different and unrelated story. There is a special charging mode where the charger does only charge and not supply the OMAP until the battery has been significantly charged. Then, there is collected enough energy in the battery to boot.

Does the Pyra have any means of measuring the input voltage? If so, it could warn us that we have a shitty cable.
 
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