Brief Answers to the Big (Pyra) Questions


matzesu

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There is a simular Topic in the German forum.gp2x.de, (EvilDragons German Board about Gp2x Pandora, etc), so i thought this should be a great topic for your Questuions about the Pyra, mybe some small practical Questions (how hot can i clean my Pyra??), and such things..

Dotnt expect me to answer this Questions, unless i know the Answers, .., its more a Comunity Help Thread thats hopefully prevents the News Posts from Off Topic..

And Sorry to Stephen Hawkings that i use his Book Title ..
 
For the moment, while very few of us have anything resembling a finished device, might it make sense to start out by trying to pre-emptively answer the inevitable flurry of questions from potential customers?

The really difficult part (to my mind) is explaining the Pyra's best qualities without seeming too aggressive. We must remember that while the Pyra's strengths will be well-aligned to the values of this community, that doesn't go for the population at large. Most people will not, and should not buy a Pyra, because it isn't the right device for their needs.
 
Random question - that's probably already answered elsewhere, but there's one game I've never actually played, but may be likely to give a go on the Pyra is Super Tux Cart. Do we know if it will run smoothly?
 
This Thread was more meant for smal Questions in the praktical Pyra Use, something like "There is a LED one my Pyra thats Shines Blue, what dos this make ???",
Nothing that belongs in the FAQ Threadt, because its sometimes something, that happens one time just for one Member,

But if whe Think, that some Questions may be interresting for the FAQ, whe could also move they to the FAQ Suggestions Threadt,
 
With the sheer amount of different capacities and transfer speeds out there for SDXC cards, I was wondering if there's any limit to what the Pyra can use.
A 256GB SDXC with a 95 MB/s transfer speed sounds like an amazing upgrade for the internal SDXC slot.
This might be a stupid question, since they're all "Class 10", but could anyone enlighten me on this subject?
Also, do any SDcards that are not of the XC variety work?
 
SDXC mainly relates to the maximum available capacity, and it's currently the biggest (plain old SD tops out at about 2GB, and SDHC tops out at 32GB and SDXC tops out at 2TB (and since June this year there's apparently SDUC which goes further). Along with those capacities, the standards also mandate a default filesystem, but linux supports them all as far as I know, and you can always reformat them if you want to.

There's also the UHS interface standard, which is largely orthogonal to the main type rating, since it's about the physical interface and frequency, while the main type is more about the data packets and formatting. There's UHS-I to III (III was announced in February apparently), but UHS-II cards are still quite rare in my experience. They Pyra only support UHS-I cards.

I don't think anyone's actually done real-world speed ratings on maximum SD storage yet, but it's probably limited by some other part of the chain that uses the data on the cards. IIRC just dumping data to null topped out at about class 6 on the Pandora for example, despite the SD slots physically being capable of pulling data off as class 10 speeds if it were possible.

Plus most speed ratings on cards are the theoretical burst maximum, I think the old speed classes mandated steady read speeds at a number of megabits per second, but they said nothing about write speeds.
 
If you want to know about sd cards for SBC , check out (google) armbian iozone
They have the most experience with uSD for SBC
In short, for SBC 95% of uSD are shit,,, Sd card were/are made for cameras, single threaded,
1 long write (or read).. There are other peculiarities (eg, no trim).
Don't ever fill a card more than 90%, less is better
Armbian uses zram for swap with 10 minute writes, to reduce wear
Get a A1 card or any evo (large is better), check for fakes as soon as you get it,, f3 or htestw
SD high speed tops at 50 Mhz, UHS1 200 Mhz (all x 1/2 byte). This is the speed of the socket, not card
*SBC -- small board computer
 
I have a USB key designed to store data on my keyring, and I tested that as an 8GB part using f3write/read, but when I checked the drive after writing a stick full of my own data a few weeks later, the first 8192 bytes had been cleared. I've not trusted it with anything important since, but it did pass the f3 test suite, and as far as I know was always mounted and unmounted properly.
 
Thank you, levi and wdt. I'm getting a bit of an idea about this whole SD card subject now. I suppose what matters the most, is this UHS-I specification. Looks like I'll be getting more, low capacity cards, instead of investing in one big one. More bang for the buck too and I can't say the Pyra is lacking SD card slots.

Now I'm curious about the SATA capability though. I'm not sure what to search on in that regard. Could someone maybe point me to some site, with some interface that will work?
 
I don't think we've officially been told how to work the esata port, but putting bits on information together, I think you'll need the dragonbox eSATA adaptor and an eSATA to full size SATA connector and some way to power the drive. For example, I've found the following on amazon uk:


Code:
https://www.amazon.co.uk/Akasa-AK-CBSA03-80BK-Flexstor-eSATA-Cable/dp/B005GNP72M

With that and a dragonbox adaptor you can convert the blue USB 2.0 port and another USB 2.0 port into a full size powered SATA connector which you can just plug into a bare SATA drive which should then spin up and become mountable.

Perhaps the dragonbox connector actually supplies eSATAp which is powered, by using the 5V from the USB lanes, I can't remember. But the linked cable above should work either way, even if you could use an eSATAp to full-sized SATA cable which doesn't come with the USB y-cable.
 
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