2020-05-01

PC-802 Android 2.2 8" tablet

Cheap, "no name" PC-802 tablet based on Android 2.2/Froyo.
Received as "partially working" - stuck on Android boot screen.

 Opening: two screws under plastic element partially covering speakers, two screws under sticker. Relatively easy to open latches on all four sides.



 Two 463985 cells, 1800 mAh each. Still holding reasonable charge.

 WM8650 from WonderMedia - 600 MHz ARM926EJ-S, single core mounted on separate PCB module. Apparently hundreds of different tablets and "mini-PCs" were based on it back in 2010-2012.
Samsung K9GAG08U0E - 16Gbit MLC (2 bits/cell) NAND Flash.
2 x ELPIDA E1108AFSE-8E-F DDR2 DRAM - apparently used also in PC memories.
Exposed JTAG pads.
 WM8900L - low power input/output audio codec with microphone amplifier, analog mixing capabilities, supporting I2S.

 VIA VT6113 Ethernet PHY.
 S16011G ethernet transformer. Apparently ethernet can connected through wide, proprietary connecter at the edge.




 WiFi on separate module, apparently connected through USB.

 UOR6153 - controller for resistive touch screen, working along with Semico CS7146.

 Stucking on boot screen seemed like typical NAND bit rot - 10 years would be close to declared NAND data retention time and also problems with NAND probably were less known back then as testing this takes time.
Loading Uberoid for WM8650 fixes the problem:
https://www.mobilarian.com/showthread.php?t=877342




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