On Wed, Apr 8, 2015 at 9:33 AM, Robert P. J. Day <[email protected]> wrote: > On Wed, 8 Apr 2015, Robert Nelson wrote: > >> On Wed, Apr 8, 2015 at 9:14 AM, Robert P. J. Day <[email protected]> >> wrote: >> > >> > seeing differing opinions online ... if you read this: >> > >> > https://e2e.ti.com/support/arm/sitara_arm/f/791/t/233139 >> > >> > i should be able to display the first few bytes of the BBB's EEPROM >> > from u-boot using: >> > >> > i2c md 0x50 0 16 >> > >> > but, for me, that just displays "ff" throughout, which is what *other* >> > people claim to see when they try it. >> > >> > should this command work? do i need to initialize something first? >> > am i (theoretically) using the correct arguments? >> >> U-Boot# i2c probe >> Valid chip addresses: 24 34 50 >> U-Boot# i2c md 0x24 0 16 >> 0000: e2 3f 00 01 b1 80 b2 01 00 00 08 00 7f 0c 18 11 .?.............. >> 0010: 09 06 09 38 26 3f ...8&? >> U-Boot# i2c md 0x34 0 16 >> 0000: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ >> 0010: 00 00 00 00 00 00 ...... >> U-Boot# i2c md 0x50 0 16 >> 0000: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ................ >> 0010: ff ff ff ff ff ff ...... > > ok, you're seeing what i'm seeing but shouldn't that last command > print the first 16 bytes of the EEPROM (header, board name, version)? > if i boot into linux, and: > > # cd /sys/devices/ocp.3/44e0b000.i2c/i2c-0/0-0050 > > then i can certainly dump what corresponds to the EEPROM: > > # hexdump -C eeprom | less > 00000000 aa 55 33 ee 41 33 33 35 42 4e 4c 54 30 41 35 43 |.U3.A335BNLT0A5C| > 00000010 32 37 31 33 42 42 42 4b 37 35 37 31 ff ff ff ff |2713BBBK7571....| > 00000020 ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff |................| > ... snip ... > > so can i not do that from within u-boot?
U-Boot# i2c md 0x50 0x0c.2 000c: 30 30 30 43 32 34 31 34 42 42 42 4b 30 31 30 33 000C2414BBBK0103 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 [email protected]. For more options, visit https://groups.google.com/d/optout.
