WiPi and Pi Face

Hi Mike,

I would get the latest version of Raspbian from the Foundation's site, get wireless working on that (using the wireless config tool on the desktop) and then use the manual install guide on the 'getting started with Piface PDF' (http://www.element14.com/community/docs/DOC-53057/l/piface-get-started-guide) to manually install the software you need.

Steve

I recommend Steve's advice.  The U of Man's image isn't based on the most recent image of Raspbian.  The installation process is pretty simple.  Post if you have problems.  I've done on the current 2013-Feb-09 Raspbian image from raspberrypi.org.

I recommend Steve's advice.  The U of Man's image isn't based on the most recent image of Raspbian.  The installation process is pretty simple.  Post if you have problems.  I've done on the current 2013-Feb-09 Raspbian image from raspberrypi.org.

@fustini: Thanks for letting us know! I have a question related to the image that you've shared with us its ok to write it to a 8 GB SD card? I imagine that it won't be no problems with that...

Thanks,

Alex

Hi - yeah, you can write it to a bigger card.  The raspi-config utlitiy will allow you to expand the existing partition to take up the whole card if you'd like.

A word of caution about cards...

The class10 cards are designed for faster access, but only ONE file at a time.

Many people had issues in the earlier days with the OS not happy and it seems that the class10 may have been the cause.

I've used the cheap Class4 cards without a hitch.

Mark

Mark,

  This is really interesting about the Class10 cards.  Is it fair to guess that the Class10 cards are faster one file at a time because they are used primarily for digital cameras?  Thanks for the insights and I look foreward to any responses to my surmise.

David

David

I'm not the expert, but that's what I summise.

There was some very interesting discussions about what is inside most of the lower cost SD cards.

If I recall the issues surfaced March 2012 when the Pi became available, and are probably in the Pi site forum/blogs.

I have used Adata, Kingston, Sandisk usually Class4 and they all seem to work.

Mark

You sort of need to be careful how you interpret some of this, 'Class 10' really only says the card can support 10MB/s sequential writes. Of more interest to the Pi is what underlying write modes (1 bit, 4 bit, SPI, SDR, DDR) the card uses and what voltage (1.8v, 3.3v) and clock speeds the card needs.

The problem being that the Pi doesn't support all of the possible modes a card may support, for example the Pi can't do 1.8v, and especially in the early days there were bugs with incorrectly picking the clock speeds.  So card supports "mode A" Pi tries to use "mode B" and the mismatch caused problems, even for otherwise perfectly good cards.

You then have cards labelled as Class 10 that really want UHS or 1.8v signalling in order to do that - and the Pi can't.. So depending on what else the card does or doesn't support a very slow failsafe mode might be chosen.

The final clue is in the definition of Class 10 meaning 10MB/s sequential writes. It's not so much about a single file as it is about being able to write a file in a single sequential, contiguous block. This is perfect for cameras saving a big digital image, but may not match up with the random read/write patterns of a generic OS.

Then just after you thought you'd worked everything out you have the usual problems of it being difficult to match up the manufacturers claims with the device inside the card. The manufacturer claims the best possible theoretical performance under some ideal condidions, or you have a counterfeit card that's not what it claims to be at all.

Lots of potential pitfalls for the unwary.

These days, with a recent OS image most cards will just work. There will always be exceptions.

I've used class 4,6, 10 & UHS-1 cards with success, some of which wouldn't even allow the Pi to boot a year ago.  In general my best results are with Class 6 cards, but that's on a very small sample of available cards.

If you can be bothered there's loads of discussions on this stuff over on the RPF forums from around April/May 2012, today most of the issues have been fixed so only go looking if you have archaeological interest

Thanks for the great post, selsinork!  After I thought about it, and before I read your post, a single file transfer didn't quite add up... you shed quite a bit of insight on the issue for me!

Thanks selsinork

That explanation better describes the situation.

Sorry if I created confusion.

Mark

I don't think you created any confusion Mark, it's mostly that there's more to this particular issue than is obvious at first look.

I certainly learned a lot while looking at it, so happy to share!