On Fri, Apr 6, 2018 at 2:34 PM, Chris Green <c...@isbd.net> wrote:
> Robert Nelson <robertcnel...@gmail.com> wrote:
>> On Fri, Apr 6, 2018 at 1:17 PM, Chris Green <c...@isbd.net> wrote:
>> > Graham <gra...@flex-radio.com> wrote:
>> >>
>> >> From memory it was:
>> >>
>> >> Samsung 128GB up to 80MB/s EVO Class 10 Micro SDXC Card
>> >>
>> > Thanks, that gives me lots of 'headroom' when compared with what I'm
>> > actually likely to need/use.
>>
>> fyi: You'll need to be careful with SDXC. The am335x mmc/sdio
>> controller IP is only 100% rated for SDHC (max 32GB). (It doesn't
>> support the new SDXC voltages or all the new speeds...)
>>
>> So stick with name brand "SDXC" microSD cards and test "1" before you buy 
>> many.
>>
>> Likewise here, Samsung/Sandisk SDXC's seem to work fine.. ;)
>>
> Thanks Robert, I don't even need anything like 32Gb, my 4Gb eMMC based
> BBB (running Debian 7) is only half full still.  Debian 9 won't need
> much more space so I can still fit happily in 4Gb.
>
> My question was more to find out what microSD cards I could use for
> installing the new OS.
>
> Plus I have two older BBBs with only 2Gb which is decidedly tight so
> using a microSD card instead would provide more space so I can use
> them as backup systems.  Is there any difference in speed between eMMC
> and microSD (though presumably SD cards vary in speed)?

Well the eMMC has a 8 bit interface (1), where as the microSD only has
an 4 bit interface (2)...  However even generic microSD's can be
faster then the eMMC..  (kinda of a waste of the 8bit interface..)

1: 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/am335x-boneblack-common.dtsi#n25

2: 
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/arch/arm/boot/dts/am335x-bone-common.dtsi#n397

Regards,

-- 
Robert Nelson
https://rcn-ee.com/

-- 
For more options, visit http://beagleboard.org/discuss
--- 
You received this message because you are subscribed to the Google Groups 
"BeagleBoard" group.
To unsubscribe from this group and stop receiving emails from it, send an email 
to beagleboard+unsubscr...@googlegroups.com.
To view this discussion on the web visit 
https://groups.google.com/d/msgid/beagleboard/CAOCHtYhFzNf_p0nABjjNjC5xx9B4AiUxPDYLi27BtrYaTMmk0w%40mail.gmail.com.
For more options, visit https://groups.google.com/d/optout.

Reply via email to