Unbricking WM8650 based tablet
(PRELIMINARY VERSION - TO BE ADJUSTED 
Interface to adapt 3.3v signals to RS-232:
made as
connect here:
connect serial, use ckermit (apt-get install ckermit)
launch "ckermit" and write this:
set modem type none set line /dev/ttyUSB0 set speed 115200 connect
turn on the device, you will have a boot logo, press a key to block it or maybe you will have the
WMT #
prompt.
Have a copy of a working firmware for UBEROID, unpack it in a dir, and read the file
wmt_scriptcmd
Now, "copy & paste" line by line from your wmt_scriptcmd to the hyperterminal.
Copy & Paste only the "setenv" lines (before "fastload", "saveenv" lines) in the "WMT #" prompt, and hit ENTER after each line.
setenv kernel-NAND_ofs setenv kernel-NAND_len setenv initrd-NAND_mtd setenv initrd-NAND_ofs setenv initrd-NAND_len setenv filesystem-NAND_mtd setenv filesystem-NAND_ofs setenv filesystem-NAND_len setenv wmt.nfc.mtd.u-boot-logo setenv wmt.nfc.mtd.kernel-logo setenv wmt.display.param 2:0:16:0:0:0 setenv wmt.display.tmr 40000:0:10:46:800:20:10:23:480:10 setenv wmt.display.pwm 0:25:50:99 setenv memtotal 214M setenv wmt.display.logoaddr 500000 setenv wmt.kernel.animation.addr f600000 saveenv display init force mmcinit 0 textout -1 -1 \"WM8650 Uberoid2.2 upgrade preparing, please wait ...\" FFFF00 setenv bootargs 'mem=214M root=dev/ram0 rw initrd=0x01000000,32768K console=ttyS0,115200n8 loadtime=-4'
Now, do you see those
fatload mmc 0 1000000 FirmwareInstall/ramdisk.gz fatload mmc 0 0 FirmwareInstall/uzImage.bin
lines in that file? we need to do those uploads by serial. As this:
loadb 1000000
now press CTRL-\ C to go to Kermit console, and "send" your "ramdisk.gz" file.
if you have some error, use the SET PREFIX stuff that kermit tell you to use to solve.
now
loadb 0
and send the file "uzImage.bin", in the same way as "ramdisk.gz" above.
note: after every upload you have to write "c" to kermit to reconnect to the terminal 
After this, do a "bootm 0" and your system will boot.
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