Inet 86dz d701c

Another cheap $20-$80 tablet with a tolerable screen and an A23 processor.

= Identification =

In android, under Settings->About Tablet, you will find:
 * Model Number: A727
 * Build Number: A23_86DZ_D701C_131174.20131229

= Sunxi support =

Current status
Like all things A23, this hardware is not supported. It is however a prime target for development. For more information, check the Allwinner A23 SoC page. A boot to android looks like this on the UART console: HELLO! BOOT0 is starting! boot0 version : 3.0.0 reg_addr 0x01f00100 =0x00000000 reg_addr 0x01f00104 =0x00000000 reg_addr 0x01f00108 =0x00000000 reg_addr 0x01f0010c =0x00000000 reg_addr 0x01f00110 =0x00000000 reg_addr 0x01f00114 =0x00000000 [DRAM]ver 0.8 clk = 552 dram ok dram size =512 sum=0x4a9f75f5 src_sum=0x4a9f75f5 Ready to disable icache. Jump to secend Boot. [     0.132]

U-Boot 2011.09-rc1-dirty (Nov 30 2013 - 13:25:18) Allwinner Technology

[     0.140]version: 1.1.0 [     0.153]pmbus:   ready [     0.155]PMU: AXP221 [     0.157]PMU: AXP22x found [     0.160]PMU: bat ratio = 56 [     0.163]PMU: dcdc3 1260 [     0.166]PMU: pll1 1008 Mhz boot power:unable to find power on vol set set to default dcdc1_vol = 3000 dcdc2_vol = 1100 dcdc3_vol = 1260 dcdc4_vol = 0 dcdc5_vol = 1500 aldo2_vol = 2500 aldo3_vol = 3000 find power_sply to end dcin_exist = 2, battery_exist = 32 BATTERY_EXIST!!!! AXP_VBUS_EXIST!!! USBC_REG_ISCR = 0x40030000 axp_set_vbus_limit_pc!! dp_dm_status = 0 !!!! fel key old mode run key detect no key found no key input dram_para_set start dram_para_set end [     0.300]DRAM:  512 MiB relocation Offset is: 14b1c000 donn't initialize ther user_gpio (main_key:boot_init_gpio) [     0.446]+++++++++++++++++++test10+++++++++++++++++++++ DRV_DISP_Init: opened [     0.454]fetch script data boot_disp.output_type fail [     0.459]fetch script data boot_disp.output_mode fail [     0.464]fetch script data boot_disp.auto_hpd fail [     0.469]lcd0_para.lcd_used=1 workmode = 0 [     0.484]NAND: NAND_UbootInit NB1 : enter NAND_LogicInit not burn nand partition table! NB1 : nftl num: 2 init nftl: 0 NB1 : NAND_LogicInit ok, result = 0x0 [     1.700]sunxi flash init ok In:    serial Out:  serial Err:  serial fastboot partitions -total partitions:11- -name-       -start-       -size- boot-resource: 1000000      2000000 env        : 3000000       1000000 boot       : 4000000       1000000 system     : 5000000       28000000 data       : 2d000000      32000000 misc       : 5f000000      1000000 recovery   : 60000000      2000000 cache      : 62000000      20000000 databk     : 82000000      8000000 private    : 8a000000      1000000 UDISK      : 8b000000      0 --- base bootcmd=run setargs_nand boot_normal bootcmd set setargs_nand key 0 recovery key high 100, low 2 cant find fstbt value to be run cmd=run setargs_nand boot_normal cant open script.bin, maybe it is not exist WORK_MODE_BOOT board_status_probe [     1.794]pre sys mode sunxi_bmp_display WORK_MODE_BOOT [     1.810]Hit any key to stop autoboot:  0 read boot or recovery all [     2.143]sunxi flash read :offset 4000000, 9352034 bytes OK no signature [     2.151]ready to boot NAND_UbootExit NB1 : NAND_LogicExit [     2.153] Starting kernel ...

Manual build

 * For building u-boot, use the "" target.
 * The .fex file can be found in sunxi-boards as MANUFACTURER_DEVICE.fex

Everything else is the same as the manual build howto.

= Tips, Tricks, Caveats =

FEL mode
The Volume +/- buttons trigger FEL mode. Unfortunately, FEL mode via this method appears to be useless for dumping device info.

= Adding a serial port (voids warranty) =



Device disassembly
Unscrew 2 small screws on the button panel side. Using a plastic tool pop out the sides and pull off the cover.

Locating the UART
The test pad nearest to the right side of the SD slot is serial TX. Tx is multiplexed with pin mmc pin 0, so expect to see garbage when using an SD card.

Rx hasn't been found yet (Neither front nor back test pads nor uSD slot pins). Read-only console for now.

= Pictures =

= Also known as =


 * Azpen A727

= See also =
 * Ippo_q8h - Another cheap A23 tablet.