Re: N770 8G SDHC card without hacking MMC slot
 

Forgot to say I am flashed with the 2007HE OS if you are going to help

Thanks
craves1

Re: N770 8G SDHC card without hacking MMC slot
 

From Secure Digital card on Wikipedia: (The "condensed version" is highlighted.)

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Compatibility with 2 gigabyte and larger SD cards has been poor, due to the SD/MMC protocol's using a 32-bit address field denominated in bytes. The SDHC standard addresses this limitation by using 32-bit block addresses instead. Both SD and SDHC are traditionally accessed as 512-byte blocks on 512-byte boundaries, so the change to host software or firmware is minor but required. Before SDHC was standardized, various manufacturers "extended" the SD control block fields for their 2 GB and 4 GB cards in different ways. Those cards are incompatible with many SD and some SDHC devices, as they conform to neither standard. All SDHC readers work with standard SD cards.

Many older devices will not accept the 2 GB size even though it is in the revised standard. The following statement is from the SD association specification:

"To make 2 GByte card, the Maximum Block Length (READ_BL_LEN=WRITE_BL_LEN) shall be set to 1024 bytes. However, the Block Length, set by CMD16, shall be up to 512 bytes to keep consistency with 512 bytes Maximum Block Length cards (Less than and equal 2 Gbyte cards)."

Since all cards up to and including the 1 GB card use a fixed 512 block size, some device drivers do not handle the larger block size and will not even recognize the 2 GB card. For example, the SanDisk web site shows examples of devices such as the iPAQ 1910 that will support only 1 GB cards and the Epson Photo RX300 Technical support says they support only 1 GB cards in the SD slot. Users of many early card readers have found that they also support only cards up to 1 GB.

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An extension of the SD standard, SDHC (Secure Digital High Capacity, SD 2.0), allows capacities in excess of 2 GB. SDHC cards are often formatted with the FAT32 file system, which supports partition sizes greater than 2 GB. It uses the same form factor as SD, but the SD 2.0 standard in SDHC uses a different memory addressing method (sector addressing vs byte addressing), thus theoretically reaching a maximum capacity of up to 2048GB. SDHC cards only work in SDHC compatible devices, but standard SD cards work in both SD and SDHC devices. The SDHC trademark is licensed to ensure compatibility.

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As of early 2007, the simultaneous availability of non-standard 4 GB SD and of standards-compliant 4 GB SDHC cards, and incompatibilities between SD and SDHC have caused confusion among consumers buying memory devices.

SD and SDHC cards and devices have these compatibility issues :

* Devices that do not specifically support SDHC do not recognize SDHC memory cards.
* Some manufacturers have produced 4 GB SD cards that conform to neither the SD2.0/SDHC spec nor existing SD devices.
* Files System: SD cards are typically formatted with the FAT16 filesystem, while SDHC cards are typically formatted as FAT32. (However, both types of cards can support other general-purpose filesystems, such as ext2 for example.)

Re: N770 8G SDHC card without hacking MMC slot
 

Yes, there is definitely some value in such ready-made adapter. So where we can buy it?
There is similar guide here
http://www.internettablettalk.com/wi..._to_a_computer

Re: N770 8G SDHC card without hacking MMC slot
 

Yes, no need to paste whole text here (and to change color to unreadable one :-). There is nothing about that parity control bit and lower reliability nonsense. While the accuracy of details in this wikipedia article is not ideal it has all the important bits right and does not contradict anything I said. As you may see the compatibility isssues start already at 1GB boundary due to some manufacturers being surprised by block size over 512 bytes. 4GB cards are not worse than 2GB ones (except the FAT32 issue). Block size for 4GB cards is 2048 bytes.

Good overview is here http://www.hjreggel.net/cardspeed/special-sd.html

Re: N770 8G SDHC card without hacking MMC slot
 

THANKS, I was able to figure out how to do this with this page and some others. It was a little confusing but I got it. I am now testing the 4g SDHC. This week I will test the 8G SDHC if everything works OK I will post links to the adapter and instructions.

I used your Kernel "kernel-sdhc-48MHz-3.2006.49.tar.gz" on the first try and so far it is working. I am writing a how to for dummies which I will post a link to this week. Can you look it over and tell me if something is wrong. If so let me know where I can send it or I will just post it.

craves1

Re: N770 8G SDHC card without hacking MMC slot
 

Just in case anyone didn’t understand, I meant a How to for Dummies like me. I am new to this and it took me a while to figure out how to flash the Kernel without a computer. I had to change many things until I found out what I was doing wrong.

Status:
SDHC MicroSD card works fine. the first thing I am finding it that Windows XP mounts it like a USB hard Drive instead of a removable.

I loaded it with 3.7G of music files trough the USB connection to the 770 and it took 110 minutes.
When I try to erase any music file or music folder it says it's read only.

Swap file enabled works OK.

craves1

Re: N770 8G SDHC card without hacking MMC slot
 

Craves1,
thanks for your work on this. I am would love a simple (for Dummies like me) kit that would allow me to expand my storage on my 770. However, I have avoided the HE2007 like the plague as I have read a lot of bad press on it here. I still use OS2006. Will your kit work for those of us who still use OS2006 (Gregale)?

thanks,
Neil

Re: N770 8G SDHC card without hacking MMC slot
 

Neil

Neil

It should work on OS2006 also. The memory converter Kit is the same. It is up to the SDHC support for OS2006 which I think is already done by fanoush. I will be getting another N770 to test OS2006 this week. The second one I was using for testing have the WSOD and the current one I am using to test OS2007 is working so good as a media player now I do not want to re-flash it with OS2006.
The WSOD was not caused by the memory converter but by static electricity when it was booting up and I remove the RS-MMC card. The screen driver board is right near the memory slot


There are some programs that do not work on my 2007HE but I am making a strictly media player with it so I do not need as many programs to work. I am more concern about it not crashing and for now it is about as stable as when I had OS2006 on it. I just need to get a status bar clock to work and it will be mostly complete.

Thank you for the post and I will update here when I have tested the N770 with OS2006 and 8G SDHC card.

craves1

Re: N770 8G SDHC card without hacking MMC slot
 

That sounds strange, there should be no difference. When you disconnect from PC, insert smaller card and reconnect, it is again removable? And when doing it again with 8GB one it is again fixed drive? Maybe formating the card in sdhc usb reader could help.
usb is slow, not sure if 110 minutes is normal, though. You may try to enable write caching for the drive in XP (=disable 'optimize for quick removal' in drive settings). Also after copying some data, check kernel log for possible i/o errors via 'dmesg' in terminal, there should be none such error. Setting to read only indicates some problem. How did you format the card? You should better not use File Manager in 770 but format from PC over usb or even use card reader for this operation. OS2006 or hacker edition may not support formating big cards properly.

Re: N770 8G SDHC card without hacking MMC slot
 

I did not format it at all. It came formatted with Fat 32. I figure I would try to solve this problem later today. I also used a USB reader to connect the same memory card to the computer then it mounts as a removable. When I put it back in the 770 it mounts as a USB hard drive.

I am not complaining about the time it takes to copy files. I have the same problem with my N800 when coping to the 16G cards so I installed SDHC readers in all my computers.

Also by the way soldering may no longer be required after today. I will post the results today.

Thanks for the post
Craves1