TBS A711
| TBS A711 | |
|---|---|
 | |
| Manufacturer | TBS AG |
| Dimensions | approx. 226 mm x 122 mm x 11 mm |
| Release Date | 2017 |
| Specifications | |
| SoC | A83T @ 2.0 Ghz |
| DRAM | 1 GiB LPDDR3 @ 732 MHz |
| NAND | 8 GB (eMMC) |
| Power | 6000 mAh 3.7V Li-Ion battery, AXP813 PMIC |
| Features | |
| LCD | 1024x600 (7" 16:9) |
| Touchscreen | Multitouch capacitive FT5xxx (Focaltech) |
| Audio | 3.5 mm TRRS microphone and headphone plug, internal speaker, internal microphone |
| Network | WiFi 802.11 b/g/n (Ampak AP6210), combined with BlueTooth |
| Storage | µSD, eMMC |
| USB | 3 USB2.0 internal hosts, 1 USB2.0 OTG |
| Camera | 1 MP front, 5 MP (2592x1944) rear |
| Other | Accelerometer (Bosch BMA250), magnetic sensor, GPS, light sensor, fingerprint reader |
Identification
There is nothing printed on the back of the device in the rectangle designed for it. There is "TBS" and logo on the front side.
The PCB has the following silkscreened on it:
A711 A83T V2.0 2016.01.20
In android, under Settings->About Tablet, you will find:
- Model Number: Octopus A83 F1
- Build Number: octopus_a711-eng
Sunxi support
Current status
The device is supported.
Manual build
Support in the community maintained sunxi-3.4 kernel is not planned.
Fex file patch was sent to the mailing list (https://www.mail-archive.com/[email protected]/msg21573.html).
U-Boot
Sunxi/Legacy U-Boot
Device was originally shipped with u-boot-2011.09.
Mainline U-Boot
Supported since 2018.01.
Devicetree source: sun8i-a83t-tbs-a711.dts
Defconfig: tbs_a711_defconfig
Working branch was: https://github.com/tbs-biometrics/u-boot-a711/tree/tbs/2017.07
Linux Kernel
Sunxi/Legacy Kernel
Allwinner kernel 3.4.39 was used.
Mainline kernel
Starting 4.15 there is sun8i-a83t-tbs-a711.dts devicetree source in mainline.
Working branch for basic support: https://github.com/tbs-biometrics/linux-a711/tree/tbs/4.13
Working branch for CSI support: https://github.com/megous/linux/tree/linux-tbs
Tips, Tricks, Caveats
LCD and touch issues
There were a few revisions of the board. The changes were in the LCD timing (timing changes just in the fex file) and a touchscreen configuration (ctp_exchange_x_y_flag and ctp_revert_*_flag were inverted).
FEL mode
There is a footprint labeled UBOOT on the board. It is located near the CPU. It is not tested but it should be usable to go into the FEL mode.
Adding a serial port (voids warranty)
There is an easily accessible UART receptacle on the board (you need to disassemble the tablet to access them).
Device disassembly
- There are four screws on the sides of the tablet. Unscrew them.
- You need to pop the pins to remove the back side. Plastic tool is very helpful.
Locating the UART
UART recetacle is labeled UART0 and it is located near the soldering pads for vibrator. It operates at 3 V. See the image for the pin assignment and UART howto for more information.
Pictures
Miscellaneous
Some tablets were donated to the community. The number of tablets for community is limited now (this may change in the future). See https://www.mail-archive.com/[email protected]/msg21568.html.