BBB: "sd" command

Jarielle Catbagan jcatbagan93 at
Tue Aug 4 00:46:14 UTC 2015

Hi Ed,

On Mon, Aug 3, 2015 at 5:14 PM, Ed Sutter <edsutterjr at> wrote:
> Jarielle,
> Very nice!
> Not sure how you tested it, but here's what I did:
> To test "sd read"...
> I first rebuilt uMon with Xmodem enabled (config.h: INCLUDE_XMODEM set).
> I ran "sd read 0x8000b000 0 100" to pull the first 100 blocks from SD to
> ram.
> Then I used xmodem to pull the same rawboot.bin image file into ram at
> 0x80100000.
> I ran "cm -v 0x80100000 0x8000b000 50680" to verify that the image I
> downloaded
> using Xmodem was identical to the image I pulled in from the SD card.
> Perfect match!
> To test "sd write"...
> I rebuilt uMon with verbose help enabled (config.h: INCLUDE_VERBOSEHELP
> set).
> I downloaded the new rawboot.bin file to 0x80100000.
> I used "sd write" to put that data into the base of the SD card.
> I was then able to reset the board and run "help sd" to see the verbose help
> message.
> So, not only did the sd-write succeed, but we're now able to update without
> removing
> the uSD card from the board!!!

Glad to hear that it's working!  :-)

I ran some tests as well but not as elaborate as yours, your tests
were better as it really put the "sd" command to the test.  The basic
sequence I did was

dm 0x80106000
sd write 0x80106000 160 2
fm 0x80106000 0x80106400 0
dm 0x80106000
sd read 0x80106000 160 2
dm 0x80106000

> Good stuff!!!
> I'm almost getting tired of saying this (just kidding)...
> Great job!
> Its in the master.
> Ed


I am almost done with the interface to the onboard eMMC, and I'll most
likely be submitting the patches tomorrow, if not earlier.

>> These series of patches implement the "sd" command with initialization,
>> reading, and writing
>> functionality.  The motivation for the implementation of the "sd" command
>> in the BBB port was to
>> avoid any modification to the core files as of right now.  The SD
>> interface utilizes the SD mode
>> as opposed to the currently implemented SPI mode SD interface in uMon.
>> Future plans include
>> integrating the SD mode implementation with the core files.
>> _______________________________________________
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