Getting access to u-boot
Follow below steps to get access to the bootloader of your device.
Contents
Prior to boot-process
- Enter Service Menu ( quickly push [INFO] [MENU] [MUTE] [POWER] on your remote control )
- Change setting for your RS232C interface to "debug" ( Control -> Sub Option -> RS-232 Jack -> [ Debug | UART | Logic ] )
- Change setting for Watchdog to "off", so that the device doesn't reboot while you are in uBoot menu ( Control -> Sub Option -> Watchdog -> [ on | off ] )
Terminal Connection Parameters
- Use following connection parameters with your terminal-client ( e.g. Kermit, Hyper Therminal or ZOC Terminal ):
Baudrate: 115200 Data bits: 8 Parity: none Stop bits: 1 Flow Control: none
For Older models (like B530), you can try lower baudrates (like 9600 bps)
During the boot-process
- Press and hold "~"
- once you see "Hit any key to stop autoboot: ..." hit ENTER ( by default there is a booting delay of 2 seconds )
Now you should have a boot prompt as show below.
Example output of the bootloader on a UExxB7000
U-Boot 1.1.6 (Dec 12 2008 - 15:55:34)
DRAM: 128 MB
**************** device info *******************
nPgsPerSLCBlk = 128
nPgsPerMLCBlk = 256
nSctsPerPg = 8
nNumOfUsBlks = 994
OneNAND[booting] mode / clk = S / 50Mhz
*************************************************
TinyBML[0] open success
env_relocate_spec
Success loading partition
Environment Data loading success!!
No ethernet found.
In: serial
Out: serial
Err: serial
Net: RTL8139#0
Hit any key to stop autoboot: 0
===============================
===============================
BOOTROM DEBUG SESSION
===============================
1. ENVIRONMENT SETUP
2. SHOW PARTITION
===============================
0. JUMP TO UBOOT PROMPT
r. REBOOT
===============================
===============================
SELECT COMMAND:
Output from "2. SHOW PARTITION" shows the partitions as listed below:
<< CS0 PARTITION INFORMATION >>
======================================================================================
description load addr id attr first_blk no_blks
======================================================================================
0 : boot loader 0x60100000 (0x00000000) SLC (0x9001) 0 1
--------------------------------------------------------------------------------------
1 : u-boot 0x60200000 (0x00000001) SLC (0xd401) 1 1
--------------------------------------------------------------------------------------
2 : u-boot env 0x60300000 (0x00000002) SLC (0x9001) 2 1
--------------------------------------------------------------------------------------
3 : update util 0x60400000 (0x00000003) SLC (0x9001) 3 1
--------------------------------------------------------------------------------------
4 : kernel image 0x61000000 (0x00000004) SLC (0xd001) 4 8
--------------------------------------------------------------------------------------
5 : root file system 0x61400000 (0x00000005) SLC (0x9001) 12 8
--------------------------------------------------------------------------------------
6 : boot modules 0x61800000 (0x00000006) SLC (0x9001) 20 4
--------------------------------------------------------------------------------------
7 : driver+exeDSP 1 0x70000000 (0x00000007) MLC (0xa001) 24 60
--------------------------------------------------------------------------------------
8 : appdata+cmmLib 1 0x78000000 (0x00000008) MLC (0xa001) 84 45
--------------------------------------------------------------------------------------
9 : driver+exeDSP 2 0xffffffff (0x00000009) MLC (0xa001) 129 60
--------------------------------------------------------------------------------------
10 : appdata+cmmLib 2 0xffffffff (0x0000000a) MLC (0xa001) 189 45
--------------------------------------------------------------------------------------
11 : mtd_tlib rw 0xffffffff (0x00000014) MLC (0xa101) 234 450
--------------------------------------------------------------------------------------
12 : mtd_rwarea rw 0xffffffff (0x00000015) MLC (0x2101) 684 42
--------------------------------------------------------------------------------------
13 : mtd_infolink rw 0xffffffff (0x00000016) MLC (0x2101) 726 150
--------------------------------------------------------------------------------------
14 : OTA rw 0xffffffff (0x00000017) MLC (0x2101) 876 118
--------------------------------------------------------------------------------------
======================================================================================
<< CS1 PARTITION INFORMATION >>
======================================================================================
Device[1] not opened
Output from "1: ENVIRONMENT SETUP" with very interesting environment variables:
------------------------------ - ENVIRONMENT SETUP - ------------------------------ 1. BOOTING COMMAND = bbm load fkernel;go 60008000 2. BOOTING DELAY = 2 3. TARGET IP = 10.88.23.246 4. SERVER IP = 10.88.27.160 5. GATEWAY IP = 10.88.23.1 6. ETHERNET ADDRESS = 10:11:12:13:14:15 7. BOOTING ARGS = root=139:6 rw ethaddr=10:11:12:13:14:15 ip=10.88.23.246 :10.88.27.160:10.88.24.1:255.255.255.0::eth0 console=ttyS1 8. UPDATE BOOTING ARGS ------------------------------ s. SAVE ENVIRONMENT x. EXIT ------------------------------
The available uBoot commands are shown via "0. JUMP TO UBOOT PROMPT":
LEONID # help ? - alias for 'help' mtest - simple RAM test autoscr - run script from memory base - print or set address offset bbm - BBM sub-system bdinfo - print Board Info structure boot - boot default, i.e., run 'bootcmd' bootd - boot default, i.e., run 'bootcmd' bootm - boot application image from memory bootp - boot image via network using BootP/TFTP protocol cmp - memory compare coninfo - print console devices and information cp - memory copy crc32 - checksum calculation echo - echo args to console fatinfo - print information about filesystem fatload - load binary file from a dos filesystem fatls - list files in a directory (default /) go - start application at address 'addr' help - print online help iminfo - print header information for application image itest - return true/false on integer compare jade - loadb - load binary file over serial line (kermit mode) loads - load S-Record file over serial line loady - load binary file over serial line (ymodem mode) loop - infinite loop on address range md - memory display mm - memory modify (auto-incrementing) mtest - simple RAM test mw - memory write (fill) nfs - boot image via network using NFS protocol nm - memory modify (constant address) pci - list and access PCI Configuration Space ping - send ICMP ECHO_REQUEST to network host printenv- print environment variables rarpboot- boot image via network using RARP/TFTP protocol reset - Perform RESET of the CPU rtl8139_eeprom - read & print out eeprom contents rtl8139_eth_addr <mac addr> - write new mac address to eeprom. rtl8139_eth_init - write 0xffff into eeprom rtl8139_eth_setup - write default values into eeprom run - run commands in an environment variable saveenv - save environment variables to persistent storage saves - save S-Record file over serial line setenv - set environment variables sleep - delay execution for some time smctest [r|w|t] [addr]- raw access to DATARAM0 1KB(ldm/stm by 8 words) tftpboot- boot image via network using TFTP protocol usb - USB sub-system usbboot - boot from USB device version - print monitor version LEONID # fatls usage: fatls <interface> <dev[:part]> [directory] LEONID #boot[/code]
Entering "boot" from uboot menu starts over normally without issues.
Boot TV from USB using u-boot
After you get access to u-boot menu, you can boot external images from USB.
More on Boot_from_USB_using_u-boot
Flash TV partitions from u-boot
Here you can find detailed How-To restore TV from u-boot:
Recovery_of_Bricked_Device
--Dynamic1969 22:30, 4 December 2009 (UTC)
