Is there such a thing as a micro SD to RS-MMC adapter? [Archive] - maemo.org

TA-t3

04-20-2007, 03:50 AM

No, SD is basically a superset of MMC. SD has 4 data bit contacts while (old) MMC has 1, but SD interfaces can talk in 1-bit mode too. Newer MMC (MMC Plus) again have more contacts than SD, but all these interfaces can still interchange the cards. I believe the Reduced Size versions of MMC are just that, reduced size, but otherwise the same as MMC (sometimes there are reduced voltages as well, but interfaces can still work with all of them if made that way).
Look no further than the N800, which (with adapter, this is just for handling the different physical sizes) can handle the full range of SD/MMC/RS-MMC/mini-SD/micro-SD/MMC Plus.

THX1138

04-20-2007, 08:45 PM

I think Tweak was right about the protocols being different. SD devices offer backwards compatibility to MMC, but MMC devices can't use SD cards. An adaptor would make a RS-MMC sized SD card that went into MMC device. I think you would need some serious circuitry to make that work and it definitely would be bigger than the difference in physical sizes of MicroSD and RS-MMC. Just my .02

TA-t3

04-21-2007, 01:03 PM

Hm, I think you're right. I was only thinking about SD being compatible with the rest, not the other way around. On the other hand.. there are simple SD interfaces that actually read SD cards just as they would MMC cards, that is, through a 1-bit serial interface. I'm not certain if this means that MMC could read SD cards or not.

new299

08-03-2007, 07:16 AM

SD is backward compatable with MMC. So a MicroSD to RSMMC converter would work if such a thing existed. I've attached an SD card to my n770 and it works fine.

http://linuxjunk.blogspot.com/2007/08/nokia-n770-internally-mounted-sd-card.html

Karel Jansens

08-03-2007, 09:09 AM

Hedgecore

08-03-2007, 09:21 AM

I can't speak for the n880, but doesn't the door on the 770 have to be closed in order to mount the memory card? That kinda screws any sort of adapter.

Karel Jansens

08-03-2007, 09:54 AM

I can't speak for the n880, but doesn't the door on the 770 have to be closed in order to mount the memory card? That kinda screws any sort of adapter.

If you read the mod, you'll find a mini-howto (of the sketchiest of sorts, however!) on how to short out the door thingie.

In fact, with that door mod I think the 770 would accept regular SD cards without further soldering. They'd stick out of the 770's body, of course, making all sorts of useful things obsolete, like, oh: Portability, the use of the cover... But hey! You too can have a 4GB (with a non-HC card) 770!

I wonder... Isn't there some stuff inside the 770 that can be dremeled away, so the card slot can be moved up? Do we really need the CPU?

fanoush

08-03-2007, 11:43 AM

All you need now is a SDHC kernel patch for the 770 and you can plunk in an 8GB card monster.
In fact I have such kernel almost ready. Not sure about stability but week ago I tried to backport mmc stack from N800 kernel (including SDHC, high speed SD and >4GB MMC cards) to latest n770 2.6.16 and after all changes it still works with kingston 2gb mmc just fine. But what is more interesting for me is that this code from n800 kernel makes my transcend 4GB mmcplus card not working in n770 just like it doesn't work in n800 now (but works fine in n770 with 2.6.16 kernel). So now I'm in the process of merging changes again one by one and checking where it breaks. I thought N800 has some HW problem with this card but now it looks like it can be hopefully fixed in software. But if anyone wants to test this kernel with (high speed) SD or SDHC card in n770, let me know.

I was thinking about this SD mod for some time too, 4gb or bigger card in n770 would be nice and I don't remove the card anyway. I was reluctant to kill my only N770 with this mod and was also waiting for 4GB mmcmobile cards (which would make this mod pointless) but now I've got spare N770 one from expansys so I can start modding too :-)

fanoush

08-03-2007, 11:49 AM

I can't speak for the n880, but doesn't the door on the 770 have to be closed in order to mount the memory card? That kinda screws any sort of adapter.
yes with Nokia kernel, no with custom kernel with one line fix, waiting for closing the door is software 'feature'. Just comment line 694

if (cards_present)

in drivers/mmc/omap.c to make it check for cards also with doors open.

I have Transcend 4gb mmcplus card and it works in n770 without any hardware mod with doors opened and kernel with this one line fix.

Karel Jansens

08-03-2007, 12:11 PM

I have Transcend 4gb mmcplus card and it works in n770 without any hardware mod with doors opened and kernel with this one line fix.

It's dremel time then? :D

Karel Jansens

08-03-2007, 12:14 PM

In fact I have such kernel almost ready. Not sure about stability but week ago I tried to backport mmc stack from N800 kernel (including SDHC, high speed SD and >4GB MMC cards) to latest n770 2.6.16 and after all changes it still works with kingston 2gb mmc just fine. But what is more interesting for me is that this code from n800 kernel makes my transcend 4GB mmcplus card not working in n770 just like it doesn't work in n800 now (but works fine in n770 with 2.6.16 kernel). So now I'm in the process of merging changes again one by one and checking where it breaks. I thought N800 has some HW problem with this card but now it looks like it can be hopefully fixed in software. But if anyone wants to test this kernel with (high speed) SD or SDHC card in n770, let me know.

I was thinking about this SD mod for some time too, 4gb or bigger card in n770 would be nice and I don't remove the card anyway. I was reluctant to kill my only N770 with this mod and was also waiting for 4GB mmcmobile cards (which would make this mod pointless) but now I've got spare N770 one from expansys so I can start modding too :-)

Okay, I'm desperately trying to understand this...

Does this mean that if I were to use your SDHC-patched kernel in my N800 (still on working firmware, so not the latest one!), I couldn't use my non-HC 4GB cards anymore?

fanoush

08-03-2007, 12:15 PM

It's dremel time then? :D
Well mmcplus one is thinner so there is no need but I was thinking about cutting the 4gb card to half to make it fit ;-) But I guess I'd end with two 2GB pieces so there is no point since I already have 2GB mmcmobile card :-) But maybe leaving a bit longer piece and removing the door could give me 3GB?

fanoush

08-03-2007, 12:25 PM

Okay, I'm desperately trying to understand this...

Does this mean that if I were to use your SDHC-patched kernel in my N800 (still on working firmware, so not the latest one!), I couldn't use my non-HC 4GB cards anymore?
No, we are talking about n770 kernel here. I have 4gb mmcplus card that works in n770 (with doors open) but doesn't work in N800 (mentioned also here http://intr.overt.org/blog/?p=49 ). But when mmc code is backported from n800 kernel to n770 one the card stops working in n770 too! Initially I bought this card for n800 but since it wasn't working there I moved it to my Zodiac and tried it also in n770. When I find what makes this card unstable in n800 I can use it in n800 again.

new299

08-04-2007, 09:18 AM

In fact, with that door mod I think the 770 would accept regular SD cards without further soldering.

The MMC socket is actually too thin for an SD card. I think I might try replacing it with a SD card socket at some point.

But hey! You too can have a 4GB (with a non-HC card) 770!

hmm, so the 4GB SD cards are MMC compatible? didn't know that. Might have to check this out... :)

The OMAP1710 in the 770 actually has two MMC ports so it should be possible to mount something like a microSD internally and then have a full size SD socket (with the card sticking out). Only problem is that I'm not sure if the second port is exposed anywhere on the 770 (and if I remember correctly the OMAP1710 is BGA so it may be impossible to get to the pins).

memturbo

08-04-2007, 09:32 AM

one of you mentioned that it may be possible for the slot to recognise

2 cards with the proper wiring .

If so and if I could get the proper wiring for it

It wouldnt be hard to make a rear mounted sd slot .

Any one with this knowledge willing to share ?

A small extrusion made on the outside of the case in back where the NOKIA

name is located seems like a perfect place to mold a sd housing.

memturbo

08-04-2007, 10:17 AM

Seems like the master slave to allow 2 cards are in pin 1 ,2 or 7

Any one wanna chime in ?

http://img63.imageshack.us/img63/7792/untitledoo2.jpg (http://imageshack.us)

new299

08-04-2007, 12:56 PM

Seems like the master slave to allow 2 cards are in pin 1 ,2 or 7

Any one wanna chime in ?

MMC doesn't have chip select so any mod would only be compatible with SD cards. We'd also need to find an appropriate chip select line. Can this just be a GPIO line? I dunno. We also would need to get an SD card driver in to the kernel (sounds like this has been done).

A nicer option would be to use the second MMC/SD card port on the CPU, but finding this might be problematic. Is support already present in the OMAP1710 kernel for the second MMC port?

memturbo

08-04-2007, 01:41 PM

on the pinouts.ru site it showed the mmc with the same connections

and chip select the same as sd

new299

08-04-2007, 04:57 PM

on the pinouts.ru site it showed the mmc with the same connections

and chip select the same as sd

The MMCplus Application note (version 4): http://www.mmca.org/compliance/buy_spec/AN_MMCA050419.pdf says:

"The initialization procedure of MMCplus is equivalent to that of cards by standard version 3.31. The major difference is that any dedicated MMCplus host application is restriced to have only a single card slot (in order to cope with the increased frequency requirements)."

However it looks like standard MMC might be ok. Does anyone know if this is supported in the kernel?

The pinout for standard MMC according to the specification summary is:

Pin No. Name Type Description
1 RSV NC Reserved for future use
2 CMD I/O/PP/OD Command/Response
3 VSS1 S Supply voltage ground
4 VDD S Supply voltage
5 CLK I Clock
6 VSS2 S Supply voltage ground
7 DAT2 I/O/PP Data
Table 1: MultiMediaCard pad definition

from: http://www.mmca.org/compliance/buy_spec/MMC-System-Summary-v3.31.pdf

Doesn't have chip select, so may be it's done in the protocol?

fanoush

08-04-2007, 05:41 PM

MMC doesn't have chip select so any mod would only be compatible with SD cards.
I think there is a little confusion here. There are three modes of communication over SD/MMC slot.
- SPI - supported in theory by both mmc and sd cards, pins are explained for this mode on picture already mentioned, useful for some ancient hardware that can do only SPI
- MMC mode - only mmc cards can do this, preferred mode for MMC cards
- SD mode - only sd cards can do this, preferred mode for SD cards

Both SD and MMC modes are supported by N770 linux kernel, SPI not (for OMAP driver). Not sure about SD but at least MMC can have multiple cards connected to same bus (i.e. same pins). Cards have unique IDs and all listen to commands and only the one with correct ID responds to the command. SD maybe too (or maybe not) but anyway this mode is not regulary used and is now deprecated by MMC association. MMC high speed modes defined in MMC 4.x require only one card to be present. Also I think support for more cards is to be removed from linux kernel since it is really not used and only complicates things.

So to sum it up you may now connect more MMC cards to same pins but they will run in legacy MMC mode (max 20Mhz) and there may be bugs since this was never widely used. I'm also not sure about power requirements of such solution (i.e. if the slot in n770 can cope with powering two cards at once).

We'd also need to find an appropriate chip select line. Can this just be a GPIO line? I dunno. We also would need to get an SD card driver in to the kernel (sounds like this has been done).

chip select is only for SPI mode, we probably don't want to use this and the pin is missing in N770 slot anyway. As for SD driver it is already present in the kernel.

A nicer option would be to use the second MMC/SD card port on the CPU, but finding this might be problematic. Is support already present in the OMAP1710 kernel for the second MMC port?
No the support is not completely present due to missing hardware. If I understand it correctly having support for two slots in OMAP1710 CPU is not enough. You need additional hardware for powering up and driving the slot. Such second chip is missing for the second slot and if present in must be controlled from SD/MMC driver in linux kernel (i.e. powered up and down at right time) for the slot to work. Search this forum for both n770 and n800 schematics and see how SD/MMC slots are wired.

I think there are only two easy options to have cards over 2GB (current mmcmobile available maximum)
- wait for bigger mmcmobile cards (no problem with support for them)
- wire up >=4GB SD (regular,mini or micro) or MMCplus card to the slot.

new299

08-04-2007, 07:18 PM

So to sum it up you may now connect more MMC cards to same pins but they will run in legacy MMC mode (max 20Mhz) and there may be bugs since this was never widely used. I'm also not sure about power requirements of such solution (i.e. if the slot in n770 can cope with powering two cards at once).

Thanks for the info. I've connected 2 MMC cards ( http://linuxjunk.blogspot.com/2007/08/nokia-7700dual-mmcs.html ). And yep, they appear to work ok. Mind these are only 64 and 16mb cards so I guess I'm not drawing too much power from the 770.

However connecting a SD and an MMC at the same time only detected the SD. I thought SD should fall back to MMC mode if SD mode isn't supported but perhaps it's not supported for multiple devices. I might try connecting two SD cards and see what happens.

As for SD driver it is already present in the kernel.

The stock tablet 2006 kernel? Is there any way to tell if the device is running in SD or MMC mode. All devices appear as mmcblkX to me, which doesn't tell me much.

If I understand it correctly having support for two slots in OMAP1710 CPU is not enough. You need additional hardware for powering up and driving the slot. Such second chip is missing for the second slot and if present in must be controlled from SD/MMC driver in linux kernel (i.e. powered up and down at right time) for the slot to work. Search this forum for both n770 and n800 schematics and see how SD/MMC slots are wired.

ok, I guess the additional hardware could be added and the kernel patched if the pins are actually exposed somewhere. There are some pins next to the battery but I'm guessing those are probably JTAG? If anywhere they are probably under the metal shielding, I don't really fancy removing that right now.

Thanks for your help.

new299

08-04-2007, 07:39 PM

I might try connecting two SD cards and see what happens.

Didn't work, I get a bunch of CRC errors on dmesg and no cards detected.

fanoush

08-05-2007, 01:31 AM

I thought SD should fall back to MMC mode
As explained twice in this thread SD cards don't understand MMC protocol so the can't fall back to anything.

new299

08-05-2007, 08:02 AM

As explained twice in this thread SD cards don't understand MMC protocol so the can't fall back to anything.

Ah ok, I guess I got confused with them both being able to fall back in to SPI mode or something.

fanoush

08-05-2007, 01:56 PM

The stock tablet 2006 kernel?

Yes. it is same driver as MMC. There is no high speed SD (50Mhz) and no SDHC support in stock tablet kernel but otherwise it is there.

Is there any way to tell if the device is running in SD or MMC mode. All devices appear tas mmcblkX to me, which doesn't tell me much.

Well with SD card inserted it is in SD mode, check is done at runtime.
You can browse source here http://lxr.linux.no/source/drivers/mmc/?v=2.6.18
main sources are mmc.c and mmc_block.c, OMAP specific lowlevel driver is in omap.c

Thanks for your help.
Thanks for your tests. I was not sure more mmc cards would actually work, it is good to know it is possible and working.

electronbee

08-07-2007, 05:03 PM

A link:
http://focus.ti.com/general/docs/wtbu/wtbuproductcontent.tsp?templateId=6123&navigationId=11991&contentId=4670

However, that is not to say that there are traces going somewhere on the PCB.

I think an idea, that I have not seen in this thread, would be to make an insertable RS-MMC to SD adapter. Use a ribbon cable or flexible PCB or the like and mount a socket on the outside of the case. Or, if there is room within the shell mount the SD card somewhere within.

Hrmmm...

eb

hackjackal

09-06-2007, 04:46 PM

The link to the pictures of the mod came out with a "0" instead of a "-" when I did a cut and past. The link that works is:

http://linuxjunk.blogspot.com/2007/08/nokia-770-dual-mmcs.html

It sure looks interesting! Yes, a little flex circuit sneaking past the lever-cover to some sort of expansion pack sounds interesting. To keep it in place all the time would require some sort of leather style booklet case with a reinforced front to protect the LCD. That way there could be a compartment or flap somewhere in the case for the external module(s) and the reinforced foldover front would do the job of the metal slipcover in protecting the screen. No magnet, though. It would be best for those not requiring super speed, just more storage, like MP3 files for example. Then of course there is always the possibility of a custom ASIC chip to serve as an MMC to Compact Flash Hard Drive interface. Maybe some kernel tweaks to make it work, too. :-)

littlestone

09-15-2007, 05:05 PM

I wonder modifying a small MicroSD to SD adapter would work. Surfing the net I come across a cheap adapter like this:

http://img515.imageshack.us/img515/9641/sku50912sa7.th.jpg (http://img515.imageshack.us/my.php?image=sku50912sa7.jpg)

One side of the adapter is the USB insert, and the other side is SD. Without the USB portion the length is around 21mm, slightly longer than the 18mm RS-MMC standard. Someone reported that it's a bit thicker than the normal SD card, and if you crack open the case it looks like this:

http://img528.imageshack.us/img528/7479/img0459al5.th.jpg (http://img528.imageshack.us/img528/7479/img0459al5.jpg)

So if the case is removed, usb part is cut off, and glue a MicroSD onto the PCB, it might be thin enough and small enough to insert into 770's RS-MMC socket.

PS I don't want to spam the forum, so if you want to know where to buy it, google "Worlds Smallest 2-in-1 Trio TransFlash USB Card Reader".

powder2000

10-15-2007, 05:02 PM

http://2daughtersandablog.blogspot.com/2007/10/internal-mini-sd-mod-for-nokia-770.html

For all you brave folk. I did this over the weekend and it works fine. Just used an SD adapter for a Mini-SD card and mounted it inside.

TA-t3

10-16-2007, 05:30 AM

Link didn't work..

powder2000

10-16-2007, 10:37 AM

Link didn't work..

http://2daughtersandablog.blogspot.com/

sorry, this should work.

fanoush

10-16-2007, 10:56 AM

muki

10-16-2007, 11:56 AM

Gotta ask: why would you want SD when RSMMC is cheaper, at least here in the UK?

fanoush

10-16-2007, 12:17 PM

you can't buy 4GB or 8GB rsmmc :-)

muki

10-16-2007, 12:31 PM

granted, that is good enough reason ;-)

powder2000

10-16-2007, 01:48 PM

RS-MMC is not as widely available here in the US. If you are extra careful, you shouldn't have a problem leaving the door switch attached. I also used my dremel to sand out some space on the inside of the back housing where the card is installed. the card slot came out pretty easy with a pair of small pliers cutting at each mount point. I was going to go get a usb micro-SD adapter to get the slot out of but didn't. I would have to look at the dimensions but I bet it would fit in there fine. Tonight I will post a picture or two with the card mounted inside, I don't recall if I took a picture of the back housing that I used the dremel on. Basically I just outlined the card where I was going to put it and cut out the supports for that section. If you've seen the inside, you'll know what I mean by supports. Also, if you can find thin wire, I would highly recommend you use it. There isn't a lot of room in there.

On another note, I did reinstall 2006 over 2007he and it seems to be a little more stable for me. I don't know what the speed differences are but I suspect the 2007he didn't like using virtual memory on my sd card. It seemed to slow things down.

powder2000

10-16-2007, 01:54 PM

Good work, too bad you killed the door switch. :-) Also more photos of the procedure would be welcomed :-)

I am thinking about same hack for quite some time (http://www.internettablettalk.com/forums/showthread.php?p=73464#post73464) but so far had no time and when I had some I couldn't open the case
http://www.internettablettalk.com/forums/showthread.php?p=81295#post81295
:-) You had no problems with opening the case?

Well maybe killing the slot wouldn't be so bad after all but I would definitely want to leave the door switch working. How did you break it? Do you think it is possible to leave it working when being extra careful?

The bottom piece needs to come off before you start prying the two half's apart. Then you need to start at the top side or top. Once the top is apart the bottom needs to be unclipped while sliding the usb and power ports out of the slots. Use a thin piece of plastic to slide along the crack while prying. You should start unclipping connection points.

powder2000

10-16-2007, 01:54 PM

you can't buy 4GB or 8GB rsmmc :-)

Will the 770 support that large of a memory card? I thought it was 2 GB.

fanoush

10-16-2007, 03:07 PM

Will the 770 support that large of a memory card? I thought it was 2 GB.
4GB SD and MMC yes, >=4 GB SDHC not without SDHC patched kernel but such patch is not a problem. I have actually bought 4GB SDHC mini card for this mod to make and test such SDHC patched kernel. Otherwise plain SD (i.e. not HC) would be better choice for 4GB size.

Thanks for your tips for opening the case, not sure when I'll have next window of opportunity for this mod but I hope it will be easier next time thanks to the info you provided.

fanoush

10-16-2007, 03:12 PM

On another note, I did reinstall 2006 over 2007he and it seems to be a little more stable for me. I don't know what the speed differences are but I suspect the 2007he didn't like using virtual memory on my sd card. It seemed to slow things down.
2007he uses same linux kernel as 2006 so virtual memory handling and swapping is exactly the same. But still, perhaps the 2007HE stresses the memory more so such instability may be more visible.

powder2000

10-16-2007, 03:50 PM

4GB SD and MMC yes, >=4 GB SDHC not without SDHC patched kernel but such patch is not a problem. I have actually bought 4GB SDHC mini card for this mod to make and test such SDHC patched kernel. Otherwise plain SD (i.e. not HC) would be better choice for 4GB size.

Thanks for your tips for opening the case, not sure when I'll have next window of opportunity for this mod but I hope it will be easier next time thanks to the info you provided.

On another note, after finishing the hardware mod, when you go to check to see if the memory is recognized, you may have to check the virtual memory box to see the memory card. I had issues with this after I finished and thought the card wasn't recognized.

powder2000

10-17-2007, 10:36 AM

http://bp0.blogger.com/_mWIlnetsixI/RxWGxK9diWI/AAAAAAAAABw/wp1fZ9rmmEo/s400/DSCN0592.JPG

Inside the 770.

revwillie

10-27-2007, 11:55 AM

holy crap. I forgot about this thread. Thanks guys for exploring so many options. I'm going to buy two of those Worlds Smallest 2-in-1 Trio TransFlash USB Card Reader things since they are so cheap. Even if they don't work for hacking, I can use them for other stuff. TF cards are getting cheaper and cheaper.

serge48

11-06-2007, 06:18 PM

Great thread... lot of ideas and finally microSD in shortened "Trio TransFlash USB Card Reader" (thanks to littlestone) is working :p
Actually, I took disassembling instructions from (new299) new299 blog (http://linuxjunk.blogspot.com/2007/08/nokia-n770-internally-mounted-sd-card.html) The way of removing cover of RSMMC socket was there as well...

Here we go. It is possible to use good old RSMMC and shortened microSD adapter in the same (modified) slot.
MMC RS 18mm x 24mm x 1.4mm
Adapter (after removing USB part and little bit more) 19.5mm x 24mm x 2.2mm

770 mod (I failed to make lock mechanism work properly - removing cards is not easy after modification. I don't do it often anyway)
1. Disassemble (covered in new299 blog)
2. Remove RSMMC cover and lock mechanism (covered in new299 blog), don't break MMC detect switch. Switch works fine after modification.
3. Carefully bend exposed contacts. (They should be around 1mm higher)
4. Glue cover back to the plastic part of the socket, but not into original position. Cover should be 0.8-1mm higher then original.

Adapter mod:
1. Disassemble adapter. Build quality is too bad. Remove excess of glue inside. Place cover back. Make sure that plastic and contact parts on the same level.
2. Cut off USB part and around 1 mm from board and plastic cover.
3. Glue everything back. Make sure that plastic and contact parts on the same level (!!!). If not you will end up with card stuck forever inside adapter.

Currently I have only one Kingston (cheap and slow) 1G microSD for tests:
(fanoush "speedy" kernel):
~ $ uname -a
Linux Nokia-N800-48 2.6.16.27-omap1 #8 PREEMPT Mon Nov 13 21:15:26 CET 2006 armv5tejl unknown
(Kingston - slow MicroSD 1GB):
/home/user # time dd if=/dev/mmcblk0p2 of=/dev/null bs=8192 count=10000
10000+0 records in
10000+0 records out
real 0m 34.76s
user 0m 0.03s
sys 0m 2.96s
(MMC 2GB Kingston):
/home/user # time dd if=/dev/mmcblk0p2 of=/dev/null bs=8192 count=10000
10000+0 records in
10000+0 records out
real 0m 16.90s
user 0m 0.04s
sys 0m 3.41s

(original Nokia kernel)
~ $ uname -a
Linux Nokia-N800-48 2.6.16.27-omap1 #1 PREEMPT Tue Sep 19 16:46:58 EEST 2006 armv5tejl unknown
(Kingston - slow MicroSD 1GB):
/home/user # time dd if=/dev/mmcblk0p2 of=/dev/null bs=8192 count=10000
10000+0 records in
10000+0 records out
real 1m 2.02s
user 0m 0.03s
sys 0m 2.78s
(MMC 2GB Kingston):
/home/user # time dd if=/dev/mmcblk0p2 of=/dev/null bs=8192 count=10000
10000+0 records in
10000+0 records out
real 1m 0.97s
user 0m 0.07s
sys 0m 2.74s

No comments about speed testing - thank you, fanoush! (just waiting for new initfs with WLAN memory corruption fix ...)
Today is 10-th day when my main 770 is running OK using 1G microSD in adapter with boot from MMC, sorry, microSD, into 2007HE-2.

Thanks everybody again for a lot of great ideas!

serge48

PS. Still tempting to order 6G microSD (I know, I'll need new kernel), 8G card is only available for preorder in UK.
PPS. I'll put some images tomorrow. Just changed notebook and should sort it out first.

fanoush

12-07-2007, 01:38 PM

(Kingston - slow MicroSD 1GB):
/home/user # time dd if=/dev/mmcblk0p2 of=/dev/null bs=8192 count=10000
10000+0 records in
10000+0 records out
real 0m 34.76s
user 0m 0.03s
sys 0m 2.96s
(MMC 2GB Kingston):
/home/user # time dd if=/dev/mmcblk0p2 of=/dev/null bs=8192 count=10000
10000+0 records in
10000+0 records out
real 0m 16.90s
user 0m 0.04s
sys 0m 3.41s

Noticed new posts in this thread only today. SD card speed result above is twice as slow since there is no high speed SD mode in my kernel (only high speed MMCplus mode which is different). I have SD high speed mode enabled as part of my unreleased SDHC kernel. Will post some testing version soon. Check this thread (http://www.internettablettalk.com/forums/showthread.php?t=12833) for possible progress.

machinehead0

12-18-2007, 06:57 AM

I managed to use the current memory socket, by grinding down the front on my "SD to microSD" card.

I removed the Flap on the 770 and put a bit of plastic were the micro switch is. As to keep the switch on.

So I am now able to use RSMMC, MMCPlus and microSD cards

I tried to put a SD socket inside the 770, but it was to thick.

fanoush

12-18-2007, 07:33 AM

I managed to use the current memory socket, by grinding down the front on my "SD to microSD" card. Any photos of your modifications? So you only cut the adapter to make it shorter and otherwise it was thin enough?

Or you made it thinner and let the length as is?

machinehead0

12-18-2007, 11:15 PM

I only made the contact end thiner. But keep the length the same.

http://machinehead0.com/nokiamem.JPG

Note: I also added a bit of tape over the protruding end to stop the card accidentally coming out.

Is there any way to power off the memory card by the CLI. Or would this be done by unmounting it?

knchris

03-01-2008, 01:18 AM

OK, so I know this is an older thread, but I wanted to post what I did and then get a question answered. I used the "worlds smallest adapter" mentioned above by disassembling it and then just taping the micro sdhc card to the contacts with scotch/invisible tape. I know it's low tech, but it works great. With the usb portion removed, i can still close the 770's door just fine and I never had to crack open the case. (Though it is a little tight of a fit). That being said, when I pop the thing into my sd card reader on my windows box, it comes up but is readonly as if there is a lock and it is switched on. I've retaped it in different positions and compared it to a normal sd card and it doesn't look like anything is in the way of the lock position. Does anybody have any ideas? I'd love to be able to throw it in the computer, copy media files over and then swap it back into the 770.

I could just connect the 770 through usb, but then if the 770 is in USB host mode, I'll have to mess with changing to slave and host and back all the time. I guess that'd still be ok if it was easier than having to use the flasher util every time. Is there an easier way?

I could do it over WiFi, but then if I'm somewhere that it's a pain to setup...blah blah blah...

You see my dilema? Ideas anyone?

By the way, fanoush, thank you for making this possible with your patches. And thanks to everyone else for the ideas, instructions, etc...

time dd if=/dev/mmcblk0p1 of=/dev/null bs=8192 count=10000
I did the perfomance test above with 10000 bytes and it finished in under 18sec

craves1

03-08-2008, 10:02 PM

Yes I designed one for my new project to upgrade the N770 to be my next music player. It is not for everybody but we will also soon be offering memory cards already installed once I get the perfect understanding on how to easily install support for SDHC. This is the only way it is useful for production. I now use several for standard microSD cards.

craves1

speculatrix

04-28-2008, 05:50 PM

is there any scope to replace the mmc socket in the 770 with a proper transflash/micro-sd socket?

Benson

04-28-2008, 06:12 PM

That being said, when I pop the thing into my sd card reader on my windows box, it comes up but is readonly as if there is a lock and it is switched on. I've retaped it in different positions and compared it to a normal sd card and it doesn't look like anything is in the way of the lock position. Does anybody have any ideas? I'd love to be able to throw it in the computer, copy media files over and then swap it back into the 770.

The write-protect switch on an SD card is just a movable tab; no electrical contacts. It is read by a microswitch in card readers that support it. So either get a card reader that doesn't support it, or cut a piece of cardboard the width of an SD card, and slide that in behind the card to trip the switch.

GregFM

05-27-2008, 11:29 PM

I bought my 770 used a couple of weeks ago, and it still had the tiny stock 64MB rsMMC card.
After reading much of the wealth of information here on ITT, (and flashing to 2007HE, & fanoush's memory patch) I almost bought the cheap 3 in 1 adapter to use with microSD memory.

However, I found this page - http://jakekerber.vox.com/library/post/sd-card-dissection.html

Which suggested all I needed to do was buy a regular SD card and cut it open. I went and bought an Ativa 2GB SD card for $10, opened it up, and the insides where exactly the same as pictures in the link above.

All I had to do was cut the original plastic backing of the SD to the size of an rsMMC card, glue the memory to the backing and viola! Perfect fit.
It inserts and removes exactly the same as the original rsMMC.

I plan on buying an 8GB card soon, and I'll update on my findings.
I suspect that manufacturing processes being what they are, it is cheapest to make the smallest flash and put it in different packages.

Bundyo

05-28-2008, 01:35 AM

Please keep us updated on the 8GB ones :)

RitchieB

06-22-2008, 08:55 AM

Has anyone seen this yet?

http://cgi.ebay.co.uk/4GB-4G-4GO-4-GB-G-GO-DV-RS-MMC-FLASH-MEMORY-CARD-UK-NEW_W0QQitemZ330240658303QQihZ014QQcategoryZ98876Q QrdZ1QQssPageNameZWD1VQQcmdZViewItem

Looking at the feedback, there has been some issues with card, but there is also some very positive feedback.

revwillie

07-21-2008, 10:57 PM

I plan on buying an 8GB card soon, and I'll update on my findings.

any findings yet?

Dibblah

09-10-2008, 05:25 AM

Many people have talked about fitting a full-sized SD slot, but I haven't seen any posts of results yet.

Here's a walkthrough of my attempt at this modification:
http://dibblah.pwp.blueyonder.co.uk/N770-SD

Cheers,

Allan.

fanoush

09-10-2008, 07:11 AM

Here's a walkthrough of my attempt at this modification:
http://dibblah.pwp.blueyonder.co.uk/N770-SD

Nice. Wiring door switch to write protect switch is not ideal though. It works when inserting card as expected but not when removing card. Opening door unmounts /media/mmc1 (possibly doing some cached writes before unmounting) and warns you if card is locked (=umount failed, file on card is used). With this wiring card is gone before writing data and unmounting so one should unmount by hand before removing the card.

jld

09-18-2008, 02:44 PM

Hi so I just cut open a 4g and it will work perfectly fine?Thanks!!

ming387

10-22-2008, 02:58 PM

Hi so I just cut open a 4g and it will work perfectly fine?Thanks!!

Which 4GB SD Card did you use? I would like to buy a card and try opening it as well. Thanks!

speculatrix

11-12-2008, 05:52 PM

anyone else bought a regular SD card, and chopped it down to fit? now that they're become quite cheap, it's not such an expensive proposition!

speculatrix

11-12-2008, 05:54 PM

I just discovered this: http://linitx.com/viewproduct.php?prodid=11141

put an SD card into an RS-MMC slot. snag is, the SD card would stick out from your 770 by a very long way!

--edit-- sorry, guys, I got confused between miniSD and mini/rs- MMC. the following article might be of interest.
http://www.oesf.org/forum/index.php?showtopic=23303&hl=menagerie

Karel Jansens

11-12-2008, 06:35 PM

I just discovered this: http://linitx.com/viewproduct.php?prodid=11141

put an SD card into an RS-MMC slot. snag is, the SD card would stick out from your 770 by a very long way!
It also won't recognize that card, unless you perform surgery on your 770; the card door has a magnetic switch.

fanoush

11-13-2008, 02:55 AM

anyone else bought a regular SD card, and chopped it down to fit? now that they're become quite cheap, it's not such an expensive proposition!
Ideal material for such experiment is sandisk plus (http://www.sandisk.com/Products/Catalog(1096)-SanDisk_Ultra_II_SD_and_SDHC_Plus_Cards.aspx) line but why not to use microSD with at least two easy solutions documented here (3 in 1 adapter from DX or ready made 8GB card from craves1) ?

I just discovered this: http://linitx.com/viewproduct.php?prodid=11141
put an SD card into an RS-MMC slot. snag is, the SD card would stick out from your 770 by a very long way!
Looks like it is for miniSD not RS-MMC. It won't fit. They are different.

RS-MMC has same width as SD or full MMC so you can fit card directly without any adapter. It will stick out however. Also SD is a bit thicker so either you need to push hard or make it a bit thinner. Or use MMCplus cards, they are same size as SD except thinner.

It also won't recognize that card, unless you perform surgery on your 770; the card door has a magnetic switch.
Or unless you comment out 2 lines in kernel source :-)

desiv

11-17-2008, 10:21 PM

anyone else bought a regular SD card, and chopped it down to fit? now that they're become quite cheap, it's not such an expensive proposition!

I just did that and it worked great!

I got a 4GB Transcend SDHC Class 6 memory card. It was $10 from Amazon with free shipping (with a $25 purchase. We bought other stuff too :-) ).

Just got it.

Clipped off one side carefully so I could separate the card. It was half height inside. So I took off the front (with the label and the contact grooves) and cut the back in half.
(I haven't glue'd the back on yet, so it's just loose, but that's next. )

I plugged it in, powered it on, and there's memory. 3.71GB according to the Memory card tab of the Memory applet.

It was that easy!!!

Now, let's see if I can get the card back out (since I didn't glue that piece in) and then glue the cover of the card (the lower half of the back) back on. :-)

desiv

desiv

11-18-2008, 12:12 PM

Well, so far so good.
The card is still working and I can read/write to/from it without any problems.

It isn't a perfect fit. I was looking at it, and its a bit thinner (wrong word, it's a bit shorter side to side) and a bit shorter now (top to bottom). The actual thickness is about the same, maybe a tad less, but close with the back on.
As it is, when I slide it into the slot, I'm not sure it "clicks" properly and its in at a slight angle, I think because it's a bit less wide. And its tricky, but not "that" hard to remove it.

I'll look at possibly adding a bit more plastic to get it to be the same size as an old MMC.

But, for $10 and 5 minutes to get 4G... Not too shabby. :-)
I suppose, now that I know that the card is half height, I could start with another card and just cut the top off to the correct height and then dremmel it down to fit, rather than taking it all apart and trying to put it back together. :-)

desiv