Zyxel NBG-419n v2, hangs during the boot

[Z419nv2]

Hello,
The router hangs at bootloader stage without any error. This is the log from UART:

U-Boot 1.1.3 (Mar 6 2012 - 17:34:10)

Board: Ralink APSoC DRAM: 64 MB
relocate_code Pointer at: 83fb0000
spi_wait_nsec: 3c 
spi device id: c2 20 17 c2 20 (2017c220)
find flash: MX25L6405D
raspi_read: from:30000 len:1000 
.*** Warning - bad CRC, using default environment

============================================ 
Ralink UBoot Version: 3.6.0.1_a3
-------------------------------------------- 
ASIC 3352_MP (Port5<->None)
DRAM_CONF_FROM: Boot-Strapping 
DRAM_TYPE: DDR2 
DRAM_SIZE: 512 Mbits
DRAM_WIDTH: 16 bits
DRAM_TOTAL_WIDTH: 16 bits
TOTAL_MEMORY_SIZE: 64 MBytes
Flash component: SPI Flash
Date:Mar 6 2012 Time:17:34:10
============================================ 
icache: sets:256, ways:4, linesz:32 ,total:32768
dcache: sets:128, ways:4, linesz:32 ,total:16384 

 ##### The CPU freq = 384 MHZ #### 
 estimate memory size =64 Mbytes
 uboot: NBG-419N v2 Power LED...on

Please choose the operation: 
  1: Load system code to SDRAM via TFTP. 
  2: Load system code then write to Flash via TFTP. 
  3: Boot system code via Flash (default).
  4: Entr boot command line interface.
  6: To emergency. 
  7: Load Boot Loader code then write to Flash via Serial. 
  9: Load Boot Loader code then write to Flash via TFTP. 
  a: Auto load system code then write to Flash via TFTP. 
 4 
You choosed 4

 0

No matter what i choose, the result is the same.

[stj]

Re: Zyxel NBG-419n v2, hangs during the boot

bad crc = you probably need to reflash the bootloader

[Z419nv2]

Re: Zyxel NBG-419n v2, hangs during the boot

Thank you for your answer.

Without a command line interface i can't do anything, so i see two options to reflash bootloader (I'm not a specialist):
1. Trying with JTAG (I saw 14 holes header in PCB).
2. Desolder the EEPROM (It's 8 pin), and reflashing it with a programmer (like CH341A).

Any other options?

[stj]

Re: Zyxel NBG-419n v2, hangs during the boot

if you can get a full-dump i'd go with desoldering the flash.
jtag can be a pain in the ass.

[stj]

Re: Zyxel NBG-419n v2, hangs during the boot

it just got added to openwrt
https://openwrt.org/toh/zyxel/nbg-419n_v2

so you may get a dump there.