逆ハッキング開始

そして空きランドJ3にシリアルポート発見！

1-TX
2-GND
3-RX
4-Vcc(3.3V)

これを USBシリアルでPCと接続します。

IPカメラ　　　　　　　　　PC
1-TX ---------- 1kΩ------------ RX
3-RX ---------- 1kΩ------------ TX
GND ---------------------------- GND
 ※事故防止用に1kΩの抵抗を挟んでいます。

TERATERMでもいいんですが、RLoginを115200bps 8bit noneにして
電源を入れると

console init done


U-Boot 2012.10 (Apr 17 2017 - 15:53:52) for GK7102 rb sc1045 v2.00 (GOKE)

HAL:  20151223 
DRAM:  64 MiB
Flash: 16 MiB
16 MiB
NAND:  SPINAND MID = 0xff, DID = 0xffff, Data = 0x1ffffff !spinand_board_init[1581]: No support this SPI nand!
SF:    16 MiB [page:256 Bytes] [sector:64 KiB] [count:256] (MX25L12845)
In:    serial
Out:   serial
Err:   serial
Net:   arm_freq(600MHz)..............0x112032
use int MII..............
gk7101
Hit any key to stop autoboot:  2     1     0 
[PROCESS_SEPARATORS] run sfboot
[PROCESS_SEPARATORS] setenv bootargs console=${consoledev},${baudrate} noinitrd mem=${mem} rw ${rootfstype} init=linuxrc ;sf probe 0 0;sf read ${loadaddr} ${sfkernel} ${filesize}; bootm
SF:    16 MiB [page:256 Bytes] [sector:64 KiB] [count:256] (MX25L12845)
put param to memory
mem size (41)
bsb size (2)

the kernel image is zImage or Image
entry = 0xc1000000 
## Transferring control to Linux (at address c1000000)...

Starting kernel ...

machid = 3988 r2 = 0xc0000100 
Uncompressing Linux... done, booting the kernel.
[    0.000000] Booting Linux on physical CPU 0
[    0.000000] Linux version 3.4.43-gk (root@localhost.localdomain) (gcc version 4.6.1 (crosstool-NG 1.18.0) ) #16 PREEMPT Mon Apr 17 12:13:21 CST 2017
[    0.000000] CPU: ARMv6-compatible processor [410fb767] revision 7 (ARMv7), cr=00c5387d
[    0.000000] CPU: VIPT aliasing data cache, VIPT aliasing instruction cache
[    0.000000] Machine: Goke GK7102 RB_SC1045 board V2.00
[    0.000000] Memory policy: ECC disabled, Data cache writeback
[    0.000000] AHB: 0x90000000  0xf2000000  -- 0x1000000
[    0.000000] APB: 0xa0000000  0xf3000000  -- 0x1000000
[    0.000000] PPM: 0xc0000000  0xc0000000  -- 0x200000
[    0.000000] BSB: 0xc2b00000  0xf5000000  -- 0x200000
[    0.000000] DSP: 0xc2d00000  0xf6000000  -- 0x1300000
[    0.000000] hal version = 20151223 
[    0.000000] Built 1 zonelists in Zone order, mobility grouping on.  Total pages: 10414
[    0.000000] Kernel command line: console=ttySGK0,115200 noinitrd mem=41M rw rootfstype=jffs2 root=/dev/mtdblock3 init=linuxrc
[    0.000000] PID hash table entries: 256 (order: -2, 1024 bytes)
[    0.000000] Dentry cache hash table entries: 8192 (order: 3, 32768 bytes)
[    0.000000] Inode-cache hash table entries: 4096 (order: 2, 16384 bytes)
[    0.000000] Memory: 41MB = 41MB total
[    0.000000] Memory: 36760k/36760k available, 5224k reserved, 0K highmem
[    0.000000] Virtual kernel memory layout:
[    0.000000]     vector  : 0xffff0000 - 0xffff1000   (   4 kB)
[    0.000000]     fixmap  : 0xfff00000 - 0xfffe0000   ( 896 kB)
[    0.000000]     DMA     : 0xff600000 - 0xffe00000   (   8 MB)
[    0.000000]     vmalloc : 0x83000000 - 0xff000000   (1984 MB)
[    0.000000]     lowmem  : 0x80000000 - 0x82900000   (  41 MB)
[    0.000000]     modules : 0x7f000000 - 0x80000000   (  16 MB)
[    0.000000]       .text : 0x80008000 - 0x8042f000   (4252 kB)
[    0.000000]       .init : 0x8042f000 - 0x8044f000   ( 128 kB)
[    0.000000]       .data : 0x80450000 - 0x80478920   ( 163 kB)
[    0.000000]        .bss : 0x80478944 - 0x804aaa18   ( 201 kB)
[    0.000000] NR_IRQS:128
[    0.000000] >> gk7101 init irq vic1...
[    0.000000] >> gk7101 init irq vic2...
[    0.000000] gk7101 init vic...
[    0.000000] mach gk7101 init timer...