GalaxyTab2BootloaderInterface » History » Revision 2
Revision 1 (Denis 'GNUtoo' Carikli, 03/03/2021 05:08 PM) → Revision 2/5 (Denis 'GNUtoo' Carikli, 03/03/2021 05:09 PM)
h1. GT-P3100Bootloader
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h2. Boot log
At boot, when pressing the power button for a short time we get:
<pre>
$ picocom -b 115200 /dev/ttyUSB1
picocom v3.1
port is : /dev/ttyUSB1
flowcontrol : none
baudrate is : 115200
parity is : none
databits are : 8
stopbits are : 1
escape is : C-a
local echo is : no
noinit is : no
noreset is : no
hangup is : no
nolock is : no
send_cmd is : sz -vv
receive_cmd is : rz -vv -E
imap is :
omap is :
emap is : crcrlf,delbs,
logfile is : none
initstring : none
exit_after is : not set
exit is : no
Type [C-a] [C-h] to see available commands
Terminal ready
Texas Instruments X-Loader 1.41 (Jun 13 2012 - 22:11:09)
Uboot-loading from Emmc
Starting OS Bootloader from EMMC ...
</pre>
Here the device boots, but if the button isn't pressed long enough it shuts down.
When pressing it for a longer time we get:
<pre>
$ picocom -b 115200 /dev/ttyUSB1
picocom v3.1
port is : /dev/ttyUSB1
flowcontrol : none
baudrate is : 115200
parity is : none
databits are : 8
stopbits are : 1
escape is : C-a
local echo is : no
noinit is : no
noreset is : no
hangup is : no
nolock is : no
send_cmd is : sz -vv
receive_cmd is : rz -vv -E
imap is :
omap is :
emap is : crcrlf,delbs,
logfile is : none
initstring : none
exit_after is : not set
exit is : no
Type [C-a] [C-h] to see available commands
Terminal ready
Texas Instruments X-Loader 1.41 (Jun 13 2012 - 22:11:09)
Uboot-loading from Emmc
Starting OS Bootloader from EMMC ...
g_nRebootReason = 0x100000
Kernel @ 81808000 (4524144 bytes)
Ramdisk @ 82800000 (994957 bytes)
set_lcd_panel_id: panel_adc=805
*** ltn070nl01_power_on ***
lcd_pannel_id=3
AST_POWERON
</pre>
Here @AST_POWERON@ probably means that there is a GPIO that can switch between the OMAP4 UART and the modem UART, and that at some point during the boot it's switched to the modem.
I tried to type AT commands like @AT@ but I got no response. Maybe it's because I use the wrong voltage for the UART. Maybe I need to reset the modem through AT commands.
TODO:
* Measure the UART voltage somehow (output only ones and try to measure it)
* Try to see if it responds to AT reset and verbose commands