miniSD / microSD for N810 links / specs

[ArnimS]

Hello,

i'd like to start a thread for links to info and performance on minisd / microsd cards for the N810. Availability is rather scant for SDHC minisd in sleepy old germany, but there are some 4GB kingston 4 and 6M minisd cards available for just under 40 euro. I also see Sandisk microsd advertised to 8GB, but they never seem to include microsd-minisd adapters - are these standardized and purchaseable seperately?

Some speed comparisons:
http://www.hjreggel.net/cardspeed/speed-by-cards-sdc.html#cdet-ki4
http://www.valuemedia.co.uk/minisd_speed_tests.htm
http://www.valuemedia.co.uk/micro_sd_transflash_speed_tests.htm

Since card performance seems to be dependent to the controller, N810 owners might benefit from posting data on read/write speeds for their cards here. To measure this, we could use something like:

Write:
sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100;sync"

Read:
time dd if=/media/mmc1/testfile of=/dev/null bs=1M

edit: added kirby's suggested sync command - this should remove effects of memory write-cache

Speeds reported ranged from 2.5-5.5 MB/s write and 9-12 MB/s read.

Cheers,
(edit2 770 with 2006 stock kernel writing to Kingston 2GB rsmmc gives.... ..... ..... ..... 0.26 MB/s)

edit3: added jibane's cache flush command, echo 1 > /proc/sys/vm/drop_caches and put it all into the attached shellscript. You can download the script, rename speedtest.sh.txt to speedtest.sh and chmod u+x to make it executable. Currently it writes to mmc2 (internal) so edit the file and change the 3 occurrences of mmc2 to mmc1 to test a SD card.

edit4: add echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor to the command
thanks smd!

[L11]

I was just about to make a similar thread, what i really want to know is whether a MicroSDHC card will work in the N810 using an adapter (http://www.mobilefun.co.uk/product/10533.htm).. MicroSD seems to be cheaper and i'd rather have one card i could share between an N810 and my N95

[traveller604]

4 GB MicroSDHC with SD adapter works in N800 so one would think that it'll also work in N810.

Then again it's Micro to mini adapter that would be needed with N810, right? I just got a 6 GB microSDHC card for my N95. Might try if it works with N800 later on. I'm guessing it will.. I mean why wouldn't it :)

[R-R]

No reasons microSD(HC) wouldn't work, all 3 sizes are pin compatible and were made that way :-)

[hircus]

N800 came with a mini-to-full-size adapter, so hopefully N810 comes with a micro-to-mini. Does anyone know?

[ArnimS]

OK, i'm seeing people buying N810s now and NOBODY has posted info on what micro/miniSD cards they are using on them.

N810 owners: Please let us know what SD cards you are using and run the benchmarks on them!

[johnkzin]

Does anyone know what the largest MicroSD/MicroSDHC card that is supported by the N810 and 2008 OS might be?

I'm about to get my N810, and I'd like to go ahead and get a nice high capacity card for it.

[kingka]

curious as to which cards to get? what the largest size is and which is the fastest read/write. etc. can anyone help me out?

[Jerome]

I tried a standard transcend 1GB microSD card in my N800 and it works. It is very difficult to take it out from the external slot, however, as you have nowhere to grab the adapter. I posted a message about that a few days ago.

MicroSD of 6GB are available from Sandisk and 8GB should be available in a matter of days. At present, 6GB microSD is the biggest storage you can buy for the N810 as no miniSD bigger than 4GB appears to exist.

[Capt'n Corrupt]

OK, i'm seeing people buying N810s now and NOBODY has posted info on what micro/miniSD cards they are using on them.

N810 owners: Please let us know what SD cards you are using and run the benchmarks on them!

I'd help if I could, but with no N810, it's pretty difficult :). I think it would be worth everyones effort, if we contributed and kept this thread alive.

Can anybody help out? Simply type the following commands on the command line, and reply with the output.



Write test:
sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100;sync"

Read test:
time dd if=/media/mmc1/testfile of=/dev/null bs=1M

I would love to know which cards are best when making my N810 and memory purchases (hopefully) towards the end of this year.


}:^)~
YARR!

Capt'n Corrupt

[TenSpeed]

No reasons microSD(HC) wouldn't work, all 3 sizes are pin compatible and were made that way :-)

So, just to be totally clear - is there any difference between an SD adapter and an SDHC adapter (micro-mini-full size)? I know the cards are different, but will an SD (not-HC) adapter work perfectly well with an SDHC card?

[Chelli]

So, just to be totally clear - is there any difference between an SD adapter and an SDHC adapter (micro-mini-full size)? I know the cards are different, but will an SD (not-HC) adapter work perfectly well with an SDHC card?

Of course it will, these adapters are all just a passive piece of plastic with a few connectors, they just transform the size of the cards and the placement of the connectors nothing more.

[theflew]

Nokia N810
A-DATA microSDHC - Class 6 (Turbo microSD HC 4G)
SanDisk micro SD to mini SD adapter

~ $ sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100;sync"
100+0 records in
100+0 records out
real 0m 27.71s
user 0m 0.01s
sys 0m 2.23s

~ $ time dd if=/media/mmc1/testfile of=/dev/null bs=1M
100+0 records in
100+0 records out
real 0m 16.16s
user 0m 0.03s
sys 0m 1.88s

[bexley]

Thanks.

Translating that to mb/s would be helpful. Knowing if a card has its class rated correctly is all that's important to me. I'm not going to compare one Class 4 card to another for minute up/down speed differences.

So, there's no micro-to-mini adapter included with the N810? These little bastards are hard to find, and I don't want to pay more for a microSD card that happens to have a mini adapter bundeled with it.

[Capt'n Corrupt]

Nokia N810
A-DATA microSDHC - Class 6 (Turbo microSD HC 4G)
SanDisk micro SD to mini SD adapter

~ $ sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100;sync"
100+0 records in
100+0 records out
real 0m 27.71s
user 0m 0.01s
sys 0m 2.23s

~ $ time dd if=/media/mmc1/testfile of=/dev/null bs=1M
100+0 records in
100+0 records out
real 0m 16.16s
user 0m 0.03s
sys 0m 1.88s

Which card belong to these outputs? The A-DATA, or the Sandisk?


}:^)~
YARR!

Capt'n Corrupt

[penguinbait]

http://www.sandisk.com/Products/Catalog(1117)-SanDisk_microSD_andmicroSDHCCards.aspx


6GB 99$

8GB 139$

[theflew]

Which card belong to these outputs? The A-DATA, or the Sandisk?


}:^)~
YARR!

Capt'n Corrupt


A-DATA, the SanDisk was just an adapter to convert from the A-DATA microSD card size to a mini SD card size that the N810 excepts.

[theflew]

Thanks.

Translating that to mb/s would be helpful. Knowing if a card has its class rated correctly is all that's important to me. I'm not going to compare one Class 4 card to another for minute up/down speed differences.

So, there's no micro-to-mini adapter included with the N810? These little bastards are hard to find, and I don't want to pay more for a microSD card that happens to have a mini adapter bundled with it.

No micro to mini SD adapter was included, which is surprising since it would have probably cost Nokia $0.25 to include if that. I got mine off of ebay for $0.99 with $4.99 shipping. It did include two adapters - micro to mini adapter and micro to standard size SD adapters. SanDisk sells some of their micro SD cards with adapters for micro and standard SD cards.

[TenSpeed]

Slightly different note - according to Wikipedia <http://en.wikipedia.org/wiki/Microsd> there are adapters that allow the use of microSD cards in MemoryStick Duo devices. Anyone seen/used such an adapter? Would the microSD card have to be formatted differently to be used in a Sony device, say, a digital camera? After shooting, could it be read on the IT?

[gemniii42]

http://www.sandisk.com/Products/Catalog(1117)-SanDisk_microSD_andmicroSDHCCards.aspx


6GB 99$

8GB 139$

Prices will only drop
I just bought a 4GB micro for $25 from Buy.com as a BF deal.

[Glenn7500]

Slightly different note - according to Wikipedia <http://en.wikipedia.org/wiki/Microsd> there are adapters that allow the use of microSD cards in MemoryStick Duo devices. Anyone seen/used such an adapter? Would the microSD card have to be formatted differently to be used in a Sony device, say, a digital camera? After shooting, could it be read on the IT?



MicroSD To Memory Stick Pro Duo Adapter (http://www.cellphoneshop.net/mitomestprod.html)

MicroSD Adapter Set (SD, miniSD, Memory Stick Pro Duo) (http://www.semsons.com/miadsetsmime.html;_ylc=X1MDMjAyMjI3NjA5OQRfcgMyBGJ 0A2NvLTEtY2xpY2sEZHN0aQNtaWFkc2V0c21pbWUEaW5BcnJhe QMEc2kDc2Vtc29ucy1pbmMEc3JjaQNtaXRvbWVzdHByb2QEdl9 tbgNyUHJvZExpc3RBZmYEdl9vcmQDMQR2X3JpZAM1X211ZF8xM Tk2MjAzMgR2X3NuA3N0b3Jlcy5jYXJ0cmVjb3M-)

[Jerome]

Slightly different note - according to Wikipedia <http://en.wikipedia.org/wiki/Microsd> there are adapters that allow the use of microSD cards in MemoryStick Duo devices. Anyone seen/used such an adapter? Would the microSD card have to be formatted differently to be used in a Sony device, say, a digital camera? After shooting, could it be read on the IT?

I have one from Transcend.

[flamingsnot]

Just received my 8gb Sandisk Micro SDHC, bought it from mobymemory.com, also got the micro-mini sd adapter separately but as part of the same order, free next day delivery.

[ArnimS]

Nokia N810
A-DATA microSDHC - Class 6 (Turbo microSD HC 4G)

sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100;sync"
Write: 0m 27.71s = 3,61 MB/s

time dd if=/media/mmc1/testfile of=/dev/null bs=1M
Read: 0m 16.16s = 6.18 MB/s

Thanks theflew! Anybody got more tests to share?

[sparkytt]

Just received my 8gb Sandisk Micro SDHC, bought it from mobymemory.com, also got the micro-mini sd adapter separately but as part of the same order, free next day delivery.
Did your's work? Mine was not recognised ny N810. Sent it back for refund. SanDisk tech support had a look into it and after 2 days said. "I'm afraid we can be of no further assistance"

[send2cbd]

I tried a 6G Sandisk microsSD/HC in a micro-mini adapter. Card was not recognized. I next tried a 4G mini card. Worked fine.

[kingka]

hey guys, both cards I have (the 1 gig sandisk, and the 6 gig sandisk micro) didnt work...

but guess what? after I PUSHED THE CARD ADAPTER (with micro sd) INTO THE CARD SLOT HARD. it worked

make sure you push the card in hard and it should work for you. both the 1gig (which I bought just to test out) and the 6 gig. work fine. I gave the 1gig to my dad after. all cards should work. well. I know the 1gig and 6 gig sandisk works.

[fredz]

Just received my 8gb Sandisk Micro SDHC, bought it from mobymemory.com, also got the micro-mini sd adapter separately but as part of the same order, free next day delivery.

Did your 8 GB SDHC card work in the N810?

[flamingsnot]

Guys I'm currently using my 8gb MicroSDHC in my N95 as my N810 hasn't arrived yet :-/ As soon as it arrives (hopefully) today or tomorrow I'll pop it in and be sure to let you all know if it works or not and if it does I'll put up the read/write tests too.

[fredz]

Guys I'm currently using my 8gb MicroSDHC in my N95 as my N810 hasn't arrived yet :-/ As soon as it arrives (hopefully) today or tomorrow I'll pop it in and be sure to let you all know if it works or not and if it does I'll put up the read/write tests too.

Any news yet?

[flamingsnot]

Apparently it took USPS 3 bloody days to get my N810 JUST from West Virginia to New Jersey and it left the US 2 days ago. I'm resisting the urge to have a long rant. Don't think I'll get it til next week, that if I'm lucky :mad::mad::mad:

[abond]

OK, here are my results:

Write

Real 0m 35.02s
User 0m 0.01s
sys 0m 2.65s

Read

Real 0m 11.27s
User 0m 0.00s
Sys 0m 1.02s

I have a 6gig SanDisk MicroSD HC card w/mini adaptor. It was the biggest one I could find at the time...


---Aaron

[ArnimS]

OK, here are my results:

Write

Real 0m 35.02s
User 0m 0.01s
sys 0m 2.65s

2.86 MB/s

Read

Real 0m 11.27s
User 0m 0.00s
Sys 0m 1.02s

8.87 MB/s

I have a 6gig SanDisk MicroSD HC card w/mini adaptor. It was the biggest one I could find at the time...


---Aaron

Thanks for the info

[R-R]

Any news yet?

At least i can confirm that:
a sandisk 8GB microSD
-> topram micro to miniSD adapter
-> Nokia's included miniSD to SD adapter (from an n800 box)

works in an N800...

[fredz]

Apparently it took USPS 3 bloody days to get my N810 JUST from West Virginia to New Jersey and it left the US 2 days ago. I'm resisting the urge to have a long rant. Don't think I'll get it til next week, that if I'm lucky :mad::mad::mad:

Still no news?

[flamingsnot]

Still no news?Nope. Says it left the US on the 22nd December. Hasn't been updated since then :mad::(

[tz1]

http://meritline.com/minisdcards.html

I got the Kingston 4Gb:

http://meritline.com/kingston-4gb-mini-sdhc-card-class-4.html

$30.90, free standard shipping.

I haven't tried the speed test yet.

[guerby]

1/ Kingston 1GB microSD card bundled with miniSD and SD adapters (11.49 euros 19.6% VAT included): write speed 4.26 MB/s on my N810 (using Kingston miniSD adapter)

2/ SanDisk 8GB microSDHC card bundled with USB microSD reader (89.90 euros 19.6% VAT included): write speed 3.32 MB/s (using Kingston miniSD adapter)

Note 24 hours later: after filling the card it seems that I now get consistently above 4.1 MB/s write speed. May be first write is somewhat slower?

3/ For reference, /media/mmc2 (internal 2GB) of my N810: write speed 2.14 MB/s

[lma]

SanDisk 8GB microSDHC, 10 runs:

Write: 41.76, 44.60, 41.25, 40.29, 42.04, 44.82, 40.02, 42.84, 44.43, 42.74
Read: 13.27, 20.91, 20.89, 16.86, 11.20, 14.64, 20.84, 20.73, 11.21, 20.79

That translates to min/max/average rates (MB/s):
Write: 2.23/2.50/2.35
Read: 4.78/8.93/5.84

It seems that read throughput fluctuates a lot!

[yueq]

Kingston 4GB mini SDHC Flash Card Model SDM6/4GB, class 6

write:

100+0 records in
100+0 records out
real 0 m 19.91s
user 0m 0.01s
sys 0m 1.88s

read:
100+0 records in
100+0 records out
real 0 m 13.38s
user 0m 0.00s
sys 0m 1.38s

[ashes]

Kingston SDM4/4GB
4GB miniSD, Class 4

~ $ sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100; sync"
100+0 records in
100+0 records out
real 0m 31.14s
user 0m 0.03s
sys 0m 2.75s
~ $ time dd if=/media/mmc1/testfile of=/dev/null bs=1M
100+0 records in
100+0 records out
real 0m 19.36s
user 0m 0.00s
sys 0m 2.59s

[Duncan]

Also Kingston 4Gb miniSDHC, class 4 (£17.44 including delivery).

~ $ sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100; sync"
100+0 records in
100+0 records out
real 0m 31.29s
user 0m 0.02s
sys 0m 2.23s
~ $ time dd if=/media/mmc1/testfile of=/dev/null bs=1M
100+0 records in
100+0 records out
real 0m 15.45s
user 0m 0.00s
sys 0m 1.80s

N.B. All times are best of 3 runs.

[ArnimS]

Dividing 100 MB by the number of seconds (real) yields:

Kingston 4GB mini SDHC Flash Card Model SDM6/4GB, class 6
write: real 0 m 19.91s
read: real 0 m 13.38s
write: 5.26 MB/s
read: 7.47 MB/s
Kingston SDM4/4GB
4GB miniSD, Class 4
write: real 0m 31.14s
read: real 0m 19.36s
write: 3.32 MB/s
read: 5.17 MB/s
Kingston 4Gb miniSDHC, class 4... Best of 3 runs.
write: real 0m 31.29s
read: real 0m 15.45s
write: 3.20 MB/s
read: 6.47 MB/s

SanDisk 8GB microSDHC, 10 runs:

Write: 41.76, 44.60, 41.25, 40.29, 42.04, 44.82, 40.02, 42.84, 44.43, 42.74
Read: 13.27, 20.91, 20.89, 16.86, 11.20, 14.64, 20.84, 20.73, 11.21, 20.79

That translates to min/max/average rates (MB/s):
Write: 2.23/2.50/2.35
Read: 4.78/8.93/5.84

It seems that read throughput fluctuates a lot!

That casts doubt into the validity of the test. I did not see more than a few percent variance on the 770. Sure nothing else was running?

I'll be testing here also in a few days :)

[Duncan]

There is always something else running. That is why when you do timing tests like this you always have to do it several times, take the fastest and assume that the others were slower because some background process kicked in to delay them. Averaging is the wrong thing to do: only the maximum rate counts.

The write time I posted is effectively identical to the time reported by ashes: my other two runs were about 3 seconds slower. The read time is better, but the other two runs were very close to the time ashes gave, so I'm confident that the times for the Kingston card are reasonably accurate and stable. Ima's sandisk times do seem to fluctuate a lot though: perhaps there was more running in the background there than should have been.

[atlas95]

Kingston 4go class 6:
sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100; sync"
100+0 records in
100+0 records out
real 0m 41.66s
user 0m 0.00s
sys 0m 3.42s

and:
time dd if=/media/mmc1/testfile of=/dev/null bs=1M
100+0 records in
100+0 records out
real 0m 16.72s
user 0m 0.01s
sys 0m 1.80s

[jibanes]

Please carefully note that these results are insignificant because they highly depend on linux's block cache, and subsequently on the memory used (but mostly available) on the n8x0 at the time of the test. Please also note that the block device layer reads ahead when possible, so clearly, these are not super meaningful results, unless if you flush the buffer cache prior to the test and run every test with the same amount of memory available for buffer cache. The buffer cache can easily be flushed as such:

echo 1 > /proc/sys/vm/drop_caches

I also suggest some random i/o patterns rather than sequential i/o, but most importantly what would be REALLY useful is to know how many writes such or such card or brand or type of card allow, it's flash technology, therefore it has a limited amount of write cycles available, which obviously is clearly not advertised, and these numbers vary quite a lot from constructor to constructor (and often from same cards from the same manufacturer, but different revision numbers). But performing such tests are indeed destructive, although that'd be worth it.

Benchmarks in sequential i/o are somewhat useless, because as long as the card is fast enough to play a movie (the contrary would be surprising) then it's fast enough for anything you would want to do that involves sequential i/o on a flash card (unless if you're intending to put a database on such card and do some table scans). Random i/o is probably closer to what people are using these cards for. If you're just storing movies on such card, then maybe, just maybe you bought the wrong kind of device, and you should have looked for some video ipod or anything (archos, creative zen...?) preferably with a harddrive. Because the point of storing 10 movies on a card is somewhat meaningless (that's when streaming media is usually more valuable than reading from the flash card); and needless to say, the cost of a 12GB/8GB card is almost as high as the cost of 10 dvds.

If you really want to use the N8x0 as a media player (read: PMP), I suggest that you focus on attaching an external harddrive to it, which could be a 2.5in laptop drive thru the usb port, or maybe bluetooth or wifi if you have some money to spend. Obviously, then the issue of power consumption becomes a real concern as well as space occupied by the "Portable" media player. Again, if playing movies is what you're looking for, then maybe the N8x0 is not the device you should have bought.

Now, storing some mp3 on such flash device makes more sense than movies because of the limited size of such device and the fact that it doesn't have an internal hard drive. Books present little interest unless you wish to kill your eyes on such a small screen. Emulated games make some sense, although I doubt there's a high interest in carrying 5000+ games around (and if so, you should have bought a gp2x). Carrying databases such as an astronomy database, or mathematic/physics reference formula or maps or simply a subset of wikipedia does make sense as well, but for such, access time to the media is usually irrelevant because whatever needs to be searched is indexed (in a b-tree I'd hope).

Now, let me ask the N810 community, what do you intend to use your 6GB+ flash card for? Now don't get me wrong, it's fine to have your favorite movie on your flash card (as long as it's "Wargames"), I'm just saying that it somewhat defeats the purpose of flash memory.

[muki]

@jibanes: bit OT maybe. I would be using it for music, pictures, ebooks, some video, utils (yes even Windows utils), packages (for poss re-install), Squeak images and probably lots of other stuff.

[ertszi]

Kingston 2GB microSD (Transflash) SDC/2GB-2ADP
sync; time sh -c "dd if=/dev/zero of=/media/mmc1/testfile bs=1M count=100; sync"
100+0 records in
100+0 records out
real 0m 34.10s
user 0m 0.00s
sys 0m 2.07s

time dd if=/media/mmc1/testfile of=/dev/null bs=1M100+0 records in100+0 records out
100+0 records in
100+0 records out
real 0m 11.08s
user 0m 0.00s
sys 0m 1.02s

best of tree attempts

[ArnimS]

Now, let me ask the N810 community, what do you intend to use your 6GB+ flash card for?

For me, Emulators and game engines; Random access, 30MB to 3GB game data.

;) Thanks for the useful info on the cache. Maybe we can get more accurate testing programs ported from linux-land. The dd test at least does show rough correlation between class 4 and class 6 claimed performance and results.

Your point that movie/media streaming does not require a high speed card is a good one and I hope people take it into consideration.

(edit)----------------------------------
Here in Germany, I'm looking at alternate.de's offers for the:

Kingston 4GB mini SDHC Class 6, rated 6MB/s Write, 6MB/s read (the one that ppl have been testing above) for 22 euro.

or

Transcend 4GB mini SDHC 45x, rated 8MB/s Write, 7MB/s read (strange rating!) for 24 euro.

Seeing as the Transcend hasn't been tested here yet, I'm buying that one today so you guys have more data points for comparison. Tests to follow...

(edit)---------------------------------
running the modified speedtest 5x (see shellscript attachment) on internal flash gives me

Write: 47.2, 42.0, 50.5, 59.7, 50.2 sec. best: 2.38 avg: 2.00 MB/s

Read: 11.9, 11.8, 19.3, 21.3, 11.8, sec. best: 8.47 avg: 6.57 MB/s

[fredz]

N810 with 8 GB Sandisk SDHC in Kingston adapter.

Write: 37.12s or 2.70 MB/s
Read: 11.26s or 8.88 MB/s

[wwp]

Some miniSD (not SDHC) cards >2GB do work, as I expected :-).

Here an EMTEC miniSD 4GB 80x (bought in France) was detected properly and does work well (I've filled w/ media files and used them) with my N810 (OS2008: 2.2007.50-2), despite dmesg shows:

.. attempt to access beyond end of device
.. mmcblk1: rw=1, want=3932228, limit=3932160
(not particularly scary)

`df` on the empty card says:
/dev/mmcblk1p1 3985408 32 3985376 0% /media/mmc1

speedtest.sh reports approx 3MB/sec writing and 9MB/sec reading (the internal mmc2 is around 3MB/sec writing and 6MB/sec reading).

[ArnimS]

Ok more info about speedtesting...

cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor will give you your current cpu governor setting

echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor should peg the cpu to fullspeed
echo ondemand > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor should set the n8x0 back to standard speed scaling
--------------------------------------------------------------
My speedruns with 'performance' and Kingston 4GB Class 6: miniSD At 86% full capacity
57.85s / 13.31s
55.39s / 14.12s
39.02s / 13.24s
44.19s / 14.14s
42.37s / 13.40s

Best time:
2.56 MB/s write
7.55 MB/s read

Does SD get slower as it fills up?

[fanoush]

despite dmesg shows:

.. attempt to access beyond end of device
.. mmcblk1: rw=1, want=3932228, limit=3932160
(not particularly scary)

`df` on the empty card says:
/dev/mmcblk1p1 3985408 32 3985376 0% /media/mmc1

It may sound scary to someone. Looks like you have bigger partition (3985408 blocks) than size of whole card (3932160 blocks). This will cause problems sooner or later. In fact the error means that it already happened.

[tz1]

I believe the version.txt file is used for DRM or something on the Navigation subscription, and points past the end intentionally.

[Benson]

I also suggest some random i/o patterns rather than sequential i/o, but most importantly what would be REALLY useful is to know how many writes such or such card or brand or type of card allow, it's flash technology, therefore it has a limited amount of write cycles available, which obviously is clearly not advertised, and these numbers vary quite a lot from constructor to constructor (and often from same cards from the same manufacturer, but different revision numbers). But performing such tests are indeed destructive, although that'd be worth it.

Benchmarks in sequential i/o are somewhat useless, because as long as the card is fast enough to play a movie (the contrary would be surprising) then it's fast enough for anything you would want to do that involves sequential i/o on a flash card (unless if you're intending to put a database on such card and do some table scans). Random i/o is probably closer to what people are using these cards for. If you're just storing movies on such card, then maybe, just maybe you bought the wrong kind of device, and you should have looked for some video ipod or anything (archos, creative zen...?) preferably with a harddrive. Because the point of storing 10 movies on a card is somewhat meaningless (that's when streaming media is usually more valuable than reading from the flash card); and needless to say, the cost of a 12GB/8GB card is almost as high as the cost of 10 dvds.

<snip>

Now, let me ask the N810 community, what do you intend to use your 6GB+ flash card for? Now don't get me wrong, it's fine to have your favorite movie on your flash card (as long as it's "Wargames"), I'm just saying that it somewhat defeats the purpose of flash memory.

First, Flash is about as fast at random as sequential access -- it's slower than RAM by enough that loading whole addresses instead of increments isn't a major penalty, and it's not like a disk where pulling a long stream of bits off as the disk goes can be is bus-saturatingly fast, but spinning the disk a different speed (for CLV disks) and slewing the head to the new track is slow. So the benchmarks should be fairly reliable, and definitely a fair comparison between units. Any random access penalty will be bus-dependent, and thus "fair".

What I use a 6GB+ flash card for (in my N800, I don't have an N810 :)? Well, I've had it for ~2 months, and I've got:
~160 MB - Manual backup of OS2008 root partition (so I could recover manually installed progs and stuff)
~540 MB - Music, MP3s, mainly >=128kbps. More coming, but I haven't got it on yet.
~300 MB - Maemo Mapper dbs, some of world, US, state, and local area at various (appropriate) zoom levels. Still haven't downloaded all the maps I want, as I can only do this with strong wifi and plugged in. (I've only got stuff from one repo, at present, so multiply x5 or so just to get all the repos I want, much less the areas I haven't got yet.)
Total, ~1.2 GB, but it'll be a lot more with more music and WAY MORE maps. The maps, I think, are a big thing. With the N810's GPS, Maemo Mapper would be even more useful. And I want a lot of maps available.

[dubiousmike]

To remain a bit off topic, I want to use my n810 for everything. Web, music, video, reading, the occasional GPS function, reading, to pick up girls with, as a remote control to my home media. It would also be great if it could run out to the store for me, but I will temper my expectations.

I am not looking for the n810 to be a long term storage solution as a PMP. But I do want it to be a short term one. I will swap out media as I need to. if the card dies, I will buy another.

I am interested though in the possibility of using thumb drives through adapters into my micro USB...

[tz1]

I do thumb drives with the micro to mini B (see host mode made easy thread), and a mini-b to A female. Or actually I have a number of microSD keychain USB drives as well - I just leave the microSD in the thumb drive where it is protected, and swap there often several times per day instead of some other method. At MicroCenter, 8Gb thumbdrives are $29.95, and I think newegg has them for that price too.

[dubiousmike]

I do thumb drives with the micro to mini B (see host mode made easy thread), and a mini-b to A female. Or actually I have a number of microSD keychain USB drives as well - I just leave the microSD in the thumb drive where it is protected, and swap there often several times per day instead of some other method. At MicroCenter, 8Gb thumbdrives are $29.95, and I think newegg has them for that price too.

Do you do heavy access to the thumb drives? I was thinking of putting video and audio on it and am wondering if the battery life would be significantly worse playing media through the thumb drive vs a mini sd in the built in slot.

[tz1]

I've played video for a half hour. They probably don't take much more than the internal flash drives, or put differently, the backlight, processor and video take more so would be the issue in draining the battery. Of course mine say 100mA, but that is peak or worst case, so they may be trickling at a much lower level.

[sherifnix]

http://www.newegg.com/Product/Product.aspx?Item=N82E16820220295&Tpk=8gb%2bmini%2bsdhc

Class 6 8gb Mini SDHC for 38.99... doesn't get much cheaper than that.

[Mara]

http://www.newegg.com/Product/Product.aspx?Item=N82E16820220295&Tpk=8gb%2bmini%2bsdhc

Class 6 8gb Mini SDHC for 38.99... doesn't get much cheaper than that.

So now they finally have it: Where were all the 8GB miniSDHC's couple weeks ago? I shelled out $65 to get the 8GB micro SDHC with micro to mini adapter... :mad:

Maybe they will have 16GB mini SDHC's available soon. Better wait those now... :rolleyes:

[dikingx]

ok i have a N810 have a micro to mini adapter and 2 micro one is 2gig and the second is a 6gig both from sandisk and the adapter is from sandisk and it works 100% no problems i dont know why some people are having problems but it works fine for me hope this helps some one in there decision

[smg]

Reminder of the importance of CPU clockspeed for the test...

As mentionned above, CPU clockspeed affect the tests. By default, the N810 is in the "ondemand" mode, so clock speed varies between the following frequencies as needed: 165000 266000 330000 400000. So depending on what is running on your n810 during the test, you may have different result.

Notice below the different results depending on the governor and whether the CPU is idle or not...

card used : /media/mmc1 1GB Sandisk 86%full (has one 800MB Godfather-II movie on it... which plays great by the way... no dropped frames at 400x224@800kbps... no dropped frames either @1500kbps... but not enough space... hence why I am reading this thread...)

Anyway, I did three runs and average is shown

Read (real time in s for 100M file)
[1] cpufreq=performance (400MHz) : 11.3s (11.32 11.32 11.20)
[2] cpufreq=ondemand (CPU not idle) : 13.7s (14.14 11.41 15.41)
[3] cpufreq=ondemand (CPU idle) : 21.4s (21.88 21.35 21.05)
[4] cpufreq=powersave (165MHz) : 22.0s (21.88 22.16 22.08)

Write (real time in s for 100M file)
[1] cpufreq=performance (400MHz) : 17.9s (19.53 15.31 18.97)
[2] cpufreq=ondemand (CPU not idle) : 25.6s (26.04 23.39 27.42)
[3] cpufreq=ondemand (CPU idle) : 25.5s (30.33 19.26 26.80)
[4] cpufreq=powersave (165MHz) : 29.1s (28.30 31.28 27.75)


[1] echo performance > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor
[2] with DateBk5/GarnetVM running and using ~25% CPU... so CPU scales up once in a while
[3] mostly idle, CPU seems to stay at 165MHz during read test
[4] echo powersave > /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor

[ch88xy]

I just got the 16gb micro sdhc card that I ordered for my N810 (about $35 from ebay). Was surprised to find that no adapter was included. In the process of finding one to buy, I noticed that some ads specifically mentioned "for 2-8gb". I wonder if the extra 8gb will be recognized.

[ch88xy]

OK, it's Sandisk 16gb micro sdhc, and I paid $31.

[silvermountain]

Great price for 16gb, is it legit or a knock-off?

[CarlGalgano]

Does anyone know if there is a 32GB card I can use in the N810? I dont really care if its SD, micro, mini..... etc. Do I need some sort of adapter? Anyone have a link to a good source to buy one?

[nhanquy]

Does anyone know if there is a 32GB card I can use in the N810? I dont really care if its SD, micro, mini..... etc. Do I need some sort of adapter? Anyone have a link to a good source to buy one?

If you are in the US; go with newegg.com, buy.com. Don't go with unknown vendors.

32GB SDHC: http://www.buy.com/retail/usersearchresults.asp?querytype=home&qu=32+SDHC&qxt=home&display=col

But for N810, you will need a kit (http://talk.maemo.org/showthread.php?t=23205) for regular SDHC.

32GB for micro, mini: I haven't found one yet.

16GB micro: need micro-to-mini adapter (http://www.meritline.com/micro-sd-adapter---p-18744.aspx)

[CarlGalgano]

so the N810 takes a mini, not a micro?

[nhanquy]

so the N810 takes a mini, not a micro?

N810 takes mini, only takes micro inside a micro-to-mini adapter.

[CarlGalgano]

and the n810 can read an entire 32gb card?

[ch88xy]

Just received a micro to mini adapter I ordered from Meritline. Put in the Sandisk 16gb micro sdhc card that I got through ebay for $31, and viola control panel shows that I have 14.83gb on removable card.