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Posts: 9 | Thanked: 0 times | Joined on Aug 2007
#23
Originally Posted by fanoush View Post
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/2007/0...dual-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.

Originally Posted by fanoush View Post
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.

Originally Posted by fanoush View Post
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.