Raspberry Pi Forums

As I can find no references to model A's having been built as yet I was wondering how this might impact the educational release that will be coming later this year.

Both versions share the same basic hardware but the model A has half the memory and as such will the current distro's be able to effectively run on the model A or will the distro's have to be pared down to fit the model A's use.

I used package smem -w to report system memory usage and it looks like it is using 159992 used but of course this in virtual box with a Debian squeeze from Liam's tutorials and LXDE running also.

They decided for the first batch to only do model Bs as that was most of us were wanting.  For following batches I believe they are doing a percentage of As and a percentage of Bs.  So instead of the model A being available in a week or so (assuming things go well of course), you'll have to wait another month.  That's not a huge delay for what is, as you stated, an identical board hardware wise... well not identical, but you know what I mean

All of which is to say it should not affect the educational release at all.  There will still be plenty of time to optimize the model A's software.

And no, we've made sure that there won't be a problem running any of the distros we put up for download here on the A.

Not worried about when an A model will be available just was wondering if it was being factored in with all the emphasis on the model B's so far as the educational release is the most important IMHO when all is said and done.

I know the foundation has a lot of work still ahead for that release and was just concerned that the model B release is not interfering to much.

Thank you!

Vindicator said:

Both versions share the same basic hardware but the model A has half the memory and as such will the current distro's be able to effectively run on the model A or will the distro's have to be pared down to fit the model A's use.
I used package smem -w to report system memory usage and it looks like it is using 159992 used but of course this in virtual box with a Debian squeeze from Liam's tutorials and LXDE running also.


Model A really has less than half the usable memory, because of the GPU taking at least 32MiB for itself.

For testing purposes you can simulate the lack of RAM by booting a Model B with "mem=96M" in cmdline.txt.

With this configuration, the debian reference image can start LXDE with a couple of terminals and the Midori browser comfortably without swapping.

Also there's a non-zero chance that in the next month a billionaire will donate half of their fortune to the RPi Foundation so the Rev.A boards can also have 256Mb of ram.

Seriously - how much will it cost to buy a 256Mb chip instead of a 128Mb one ?

humblebundle.com managed to raise $450k+ for charity in the last weekend.

I'm willing to donate some money so that some school kids can use the 128Mb "Enhanced 3D Video Mode" on their $25 RPis instead of being stuck with the 32Mb "No Video, No 3D Video Mode" (video modes capabilities according to Gert from his description of config.txt parameters)

I'll try that in virtual box by just setting up the same image with 96Mb and see what happens.

And you'll definitely be able to buy Model As in March.

liz said:


And you'll definitely be able to buy Model As in March.



Really?

Well - she did not say what year...  So Really.

would the design of the model A be different and by how much? that"s something that"s not been answered if it had it would be in the FAQ.

tzj said:


would the design of the model A be different and by how much? that"s something that"s not been answered if it had it would be in the FAQ.



Sorry, I'm not sure what you're referring to. Do you mean will the price of the new design be more?  If so they've told us no it's still $25 (plus shipping, tax, vat).  Or do you mean will the physical design be different?  If that's the case then the answer is also no, the only difference is that the model A now also has 256MB

I am reasonably sure I read this here, but I could be wrong....

The A is not just a B with parts left off. It is a different circuit board.

Even holes cost money, so don't expect unused component holes on the A's.

Different boards is one reason the factory can not switch to A's if they don't have enough parts for B's.

rmm200 said:


I am reasonably sure I read this here, but I could be wrong....

The A is not just a B with parts left off. It is a different circuit board.

Even holes cost money, so don't expect unused component holes on the A's.

Different boards is one reason the factory can not switch to A's if they don't have enough parts for B's.



It is the same PCB.  The differences will be one USB jack instead of two and no ethernet port.  The solution is simpler than you think.  Since the IC that is used on the model B is powered internally by a USB 2.0 connection the pick and place plant will simply solder mask some jumpers from the input of where that IC would be on the model B to the traces of the physical USB port.

rmm200 said:


I am reasonably sure I read this here, but I could be wrong....

The A is not just a B with parts left off. It is a different circuit board.


I've always read the opposite: they use the same circuit board with different population options.  Model A deletes the LAN9512 USB hub IC3 and the Ethernet jack, and replaces the dual USB jack with a single USB.  Model B also deletes a bunch of passives and some LEDs.  Model A connects the BCM2835 USB port to the USB jack through R36 and R37, which are unpopulated on a Model B.  You can see this in the board photos on the Wiki.

liz said:


And you'll definitely be able to buy Model As in March.



Which year?

I have a 1930 model A in the garage my wife inherited it from her oh wait -- never mind

Do you know the mechanical measurements to make a case?

Thank's

killor said:


Do you know the mechanical measurements to make a case?

Thank's


They haven't made any yet.

I wish they would find a fried or otherwise unsalable Pi and send to Killor so he can get his cases just right, and ready for The Day... I'd love to buy one if they were on USA eBay at a buy-it-now price. All I wish is that I could get one without the Raspi logo cut into it- the board already has a logo on it, and when I look at my Raspi, I want to see it clearly. Few things are more beautiful than well- made computer guts...

Hey. Sorry for disturbing, but is there any progress going on model A? Any info?

esik said:


Hey. Sorry for disturbing, but is there any progress going on model A? Any info?


Still waiting shipping of first batch, ENORMOUS backlog of model B's so very much doubt it's even being considered at present - would be thinking Christmas time if I had to guess.

I'm guessing a bit earlier than that, production quantities are quite large if Liz's comments are anything to go by.

killor said:


Do you know the mechanical measurements to make a case?

Thank's


Its the same board as the model B, only with some components and connectors removed, for the case that means that:


There is no Ethernet connector
The USB connector is a normal single connector, so no double height connector.

esik said:


Hey. Sorry for disturbing, but is there any progress going on model A? Any info?



Good question - somewhere in March there was news that a Foundation batch of beta boards had been ordered from a UK supplier. Cant find it in the front page blogs, must be either in the chat after them or somewhere in Eben's presentations. So, ...