[Hardware Hacking General] AdamOutler:
Alright.. by hex-editing the PARAM partition, i was able to get teh device to use /dev/ttySAC2 as its default console.

Affected memory log:

ATAG_REVISION: 3 54410007 b
ATAG_CMDLINE: 77 54410009 'console=/dev/ttySAC2 loglevel=4 sec_debug.level=0 se
c_watchdog.sec_pet=5 androidboot.debug_level=0x4f4c sec_log=0x200000@0x46000000
s3cfb.bootloaderfb=0x5ec00000 sysscope=0xe5f3c9da lcdtype=0 consoleblank=0 lpc
harge=0 lpj=3981312 vmalloc=144m oops=panic pmic_info=67 cordon=203137d174f51cc
7da31044b2a6dfb05 androidboot.emmc_checksum=0 androidboot.odin_download=0 andro
idboot.bootloader=GC100XXALJF androidboot.serialno=4208fcaa2cd59fc5 snd_soc_cor
e.pmdown_time=1000'
ATAG_NONE: 0 0

Starting kernel at 0x40008000...

SWITCH_SEL(3)
<6>[ 0.000000] c0 Initializing cgroup subsys cpu
<5>[ 0.000000] c0 Linux version 3.0.31-467739 (se.infra@SEP-74) (gcc version
4.4.3 (GCC) ) #1 SMP PREEMPT Fri Nov 9 15:58:11 KST 2012
<4>[ 0.000000] c0 CPU: ARMv7 Processor [413fc090] revision 0 (ARMv7), cr=10c
5387d
<4>[ 0.000000] c0 CPU: VIPT nonaliasing data cache, VIPT aliasing instructio
:

I am able to send information through the USB port and read the information coming from the /dev/ttySAC2 device. This means there IS a hardware link, but the information is getting garbled. It's possible that it could be a different speed than I am used to.

Now, another thing. When I start the device and watch the USB port for data I'm seeing this:

adam@adam-Desktop:~$ echo "��������������������������������������������������������������������������������������������������������������������������������������������������������������������������
> "|hexdump -C
00000000 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000010 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
00000020 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
00000030 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000040 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
00000050 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
00000060 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000070 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
00000080 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
00000090 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
000000a0 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
000000b0 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
000000c0 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
000000d0 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
000000e0 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
000000f0 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000100 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
00000110 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
00000120 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000130 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
00000140 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
00000150 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000160 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
00000170 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
00000180 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
00000190 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
000001a0 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
000001b0 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
000001c0 bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf |................|
000001d0 bd ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd |................|
000001e0 ef bf bd ef bf bd ef bf bd ef bf bd ef bf bd ef |................|
000001f0 bf bd ef bf bd ef bf bd ef bf bd ef bf bd 0a 0a |................|
00000200
adam@adam-Desktop:~$

It's a repeating patern of " ef bf bd " which makes me wonder if this is some sort of signal for input of some kind.

When using a 150Kohm resistor between USB pins 4-5, the device takes about 10 seconds to boot up. This would signify that the processor is doing something. The 150Kohm resistor has traditionally be the "UART" communications resistor for the GS series... Maybe it is expecting a firmware upload. However, I am not receiving any messages about that.

In order to continue the boot-from-sd, I need someone to create a "T-Flash" image on a GS3 then make a dd image of the sdcard so I can flash it to my own. Odin is failing to flash the GCam with GS3 SBOOT. I need some help on this.