type of microSD for guruplug?

[ppmt]

I am looking at buying a microSD card for my plug

This is something which wa going to be simple but I see on web site mention of microSD and microSDHC.

The latter being not compatible (with what?).

I looked on the wiki for some clues butsaw mention of SDHC but would like to have your advise

What can/should I buy and what is the maximum size allowed? 

My long term is to use it to install linux on it rather than on the internal memory. So I guess 8Gb should be plenty.

Any info will be useful to me

[flipflip]

I bought the cheapest micro SDHC 8GB card I could find in the local electronics shop. I found it in the mobile phones accessory shelf. It was approx. 35 US$. It's a no-name brand. It works without any issues so far. It says that it is a "type class 4" one. Whatever that means. Write speed is approx. 5 MB/s.

edit: right, "class 4", not "type 4"

[fragfutter]

it propably says class 4 which is the minimum guranteed write speed of 4MB/sec.

[ppmt]

thanks for your answers.

I will go and buy an equivalent card then.

[flipflip]

With "it works" I meant that it works under Linux, i.e. I can mount and use it.
It doesn't work in u-boot, i.e. I cannot boot from it. However, I think that's more an issue of the card reader than the card itself.

[ppmt]

thanks for the clarification....I am very new to these plug thingy so I will need to read a lot (adn ask question) before I attempt to change the u-boot

but has anyone managed to get a the guruplug to boot from the microSD slot? if so does it need a special type of card?

[flipflip]

Not to my knowledge. As said, I think it's an issue with the card reader, and u-boot needs to be patched/compiled/configured so that it can use it.
But you can easily boot from the flash and still use the card for the system.

[ppmt]

As I said I need to read a lot...

would you have a link that would describe what you said:

But you can easily boot from the flash and still use the card for the system.

when you say the system...do you mean that Debian would run from the microSD after a minimal boot from the flash?

Would it require playing around with the u-boot?

[flipflip]

Yes. I have the following configuration:

- Kernel in the flash (this is also the factory default)
- root (/) filesystem in the flash (507MB)
- /var (1GB), /tmp (1GB) and /usr (6GB) filesystems on the SD card

It required some minor tweaking: I had to add a delay (ca. 10'') very early, i.e. before the /var, /usr and /tmp partitions are mounted, to wait for the usb subsystem to ready the device and the partitions.

I haven't tried to put all of it on the sd card. I'm not sure if the kernel would wait for the partitions to become ready or if there's even a boot option to specify that. One could also do a boot with an initrd (I'd prefer that anyway) that could take care of all this but that would require a reshaping of the flash partitions (not a problem) because the one where the kernel is in is too small (4MB) to hold an initrd (+2-3MB, and the kernel is already 2.5MB or so).

[ppmt]

ok. I am not sure I understood all of it but I think I got the idea

thanks a lot for your patience.

[flipflip]

for reference:

There's indeed an option to make the kernel wait a bit before trying to mount the root filesystem: rootdelay=..

There's an even better option, rootwait, that waits until the root device becomes available.

I moved my system to the sd card because nfs4 doesn't like ubifs.. i'm booting now with "roowait root=/dev/sdb2".

[NemoN]

I moved my system to the sd card...

maybe you have some howto for this? 

[guidol]

maybe you have some howto for this? 

I think "Yes, he has :-)"
Take a look at http://plugcomputer.org/plugforum/index.php?topic=1642.msg10106#msg10106