BBB Clone HW with only Serial

Hi BBB community,

We have a BBB Clone hardware with only serial UART as the only communication port to our board at the moment (USB port is not working due to hardware issues)

So this is where I am at this moment, looking for advice to go forward.

HW Description:

Chip: AM3358BZC100
eMMC: Manufacturer ID: fe, OEM: 14e, MMC version 4.41 Capacity 1.8 GiB Bus Width: 4-bit
UART Serial (only I/O to the board)
USB (broken due to hardware issues)
No SDCard expansion at all.
No I2C EEPROM
No Nand

SW Setup/Progress:

Powered up in UART boot mode
loaded u-boot-spl.bin via xmodem
then after spl is loaded, loaded u-boot.img via y-modem

Uboot prompt is alive and working:

CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
U-Boot SPL 2013.04-00017-g39e4efe (Nov 20 2014 - 15:53:43)
Could not probe the EEPROM; something fundamentally wrong on the I2C bus.
Could not get board ID.
Unknown board, assuming Beaglebone LT/Black.musb-hdrc: ConfigData=0xde (UTMI-8,
dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn)
musb-hdrc: MHDRC RTL version 2.0
musb-hdrc: setup fifo_mode 4
musb-hdrc: 28/31 max ep, 16384/16384 memory
USB Peripheral mode controller at 47401000 using PIO, IRQ 0
musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn)
musb-hdrc: MHDRC RTL version 2.0
musb-hdrc: setup fifo_mode 4
musb-hdrc: 28/31 max ep, 16384/16384 memory
USB Host mode controller at 47401800 using PIO, IRQ 0
CCCCCCxyzModem - CRC mode, 2(SOH)/369(STX)/0(CAN) packets, 8 retries
Loaded 377668 bytes

U-Boot 2013.04-00017-g39e4efe (Nov 20 2014 - 15:53:43)

I2C: ready
DRAM: 512 MiB
WARNING: Caches not enabled
Could not probe the EEPROM; something fundamentally wrong on the I2C bus.
Could not get board ID.
NAND: No NAND device found!!!
0 MiB
MMC: OMAP SD/MMC: 0, OMAP SD/MMC: 1
*** Warning - readenv() failed, using default environment

musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn)
musb-hdrc: MHDRC RTL version 2.0
musb-hdrc: setup fifo_mode 4
musb-hdrc: 28/31 max ep, 16384/16384 memory
USB Peripheral mode controller at 47401000 using PIO, IRQ 0
musb-hdrc: ConfigData=0xde (UTMI-8, dyn FIFOs, HB-ISO Rx, HB-ISO Tx, SoftConn)
musb-hdrc: MHDRC RTL version 2.0
musb-hdrc: setup fifo_mode 4
musb-hdrc: 28/31 max ep, 16384/16384 memory
USB Host mode controller at 47401800 using PIO, IRQ 0
Net: not set. Validating first E-fuse MAC
Phy not found
PHY reset timed out
cpsw, usb_ether
Hit any key to stop autoboot: 0
U-Boot#

when I do “mmc part” I got an “Unknown partition table” (which is what I expected since this is a bare metal bring up)

My goal is to load either ubuntu/debian or angstrom distro onto our BBB clone’s eMMC for further application development (and boot from the eMMC)

So what are the Next steps for me with UART as the only means communication to/from our BBB Clone to bring up any Linux Distro and flash them including MLO/Uboot to eMMC using only UART?

Please advice!

Many Thanks in advance!

Paul

I'd say, find your best in-house solder person and bug wire the other
microSD connector.

Regards,

Hi Robert,

unfortunately that won’t be possible even if the skills are amazing… the SDCARD connections aren’t even connected at the via under the BGA :frowning:

Is there really no other way of bring up Linux using only UART? (speed doesn’t matter).

Is it possible to load linux into ram via uboot’s bootz command then boot off it?

Thanks in advance again…

Paul