ASUS Transformer Prime (asus-tf201)

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ASUS Eee Pad Transformer Prime
Manufacturer ASUS
Name Eee Pad Transformer Prime
Codename asus-tf201
Released 2011
Category testing
Original software Android 3.2 to Android 4.1
postmarketOS kernel mainline grate
Chipset Nvidia Tegra 3 T30
CPU Quad-core 1.4 GHz Cortex-A9
GPU NVIDIA ULP GeForce GPU 12 cores
Display 1280x800 Super IPS+ LCD
Storage 32/64 GB
Memory 1 GB
Architecture armv7
Unixbench Whet/Dhry score 1208.1
USB Networking
3D Acceleration
Mobile data
Ambient Light
Hall Effect

This device is based on Tegra 3.
See the SoC page for common tips, guides and troubleshooting steps


  • Clamor
  • Ion Agorria

Users owning this device


The first step to do anything with the device is unlocking, with this device its done by sideloading the unlock apk from ASUS and clicking a few buttons in the app. The apk can be found on the ASUS support page.

Bootloader unlock fails with Unknown error

Contact ASUS tech support, describe the issue and provide them with information they'll request. Bootloader unlock may become available within 1-2 days after the request.

Kernel status

Android kernel

Mainline (Grate)


pmOS with mate running on Prime

How to enter flash modes

Turn tablet off if it is in the system. Then press POWER and VOL DOWN buttons till you feel the vibration. Then release the POWER only. You will enter the bootloader/fastboot. In bootloader you can navigate with VOL DOWN button and to choose option use VOL UP button.

Bootloader version

Latest bootloader for TF201 was and to use pmOS you need bootloader version of to reach this you can use flashable via TWRP bootloader packages.

Installation process

Note The bootloader doesn't handle flashing the boot and userdata partition correctly, the official firmware package flashes an "Android blob" to the staging partition with fastboot which triggers an flashing screen on the tablet which copies the data to the correct partitions. pmbootstrap has tools to pack and flash kernel correctly, no worries!

Preparing rootfs and flashing kernel:

1 $ pmbootstrap init
2 $ pmbootstrap install
3 $ pmbootstrap flasher flash_kernel

Flashing rootfs to eMMC

Preferable way of installing pmOS is installing on microSD card!
Note This may change size of your data partition. You can fix it by resizing partition in TWRP before flashing Android.

You should proceed very carefully here.

Rootfs should be flashed to the /userdata partition.

Prerequisites: TWRP, at least version 3.3.1-0, binaries for bootloader are here.

First, start TWRP (go to bootloader and choose RCK) and then continue with these instructions

1 (computer) $ pmbootstrap export
2 (computer) $ adb shell
3 (twrp) $ umount /dev/block/mmcblk0p8 <- unmounting /data partition
4 (computer again) $ adb push /tmp/postmarketOS-export/asus-tf201.img /dev/block/mmcblk0p8 <- to flash rootfs to /data partition

Hardware status (mainline)

Status Hardware Info
Y Booting boot.img has restriction of approx 8MB, which is /boot partition size.
Y Bootloader Open source bootloader U-Boot is available as alternative for stock Asus bootloader and can replace it. U-Boot can not boot downstream kernel due to TrustZone problem.
Y Panel HannStar HSD101PWW2 Rev0-A00/A01 LCD SuperIPS+ HD panel through LVDS controller.
Y HDMI output HDMI works, but max output is 1080p due to Tegra 3 limitations.
Y Touchscreen Used Atmel MXT768E touchscreen.
Y USB One full size USB 2.0 in dock or via 40pin adapter.
Y SD cards MicroSD card and full sized SD card (recognized as USB drive) in dock.
Y Internal memory eMMC by Kingston KE4BT5D6A or Hynix H26M64002BNR.
N GPS Broadcom GPS BCM4751 is used. Device itself has weak signal.
Y WiFi Uses Azurewave AW-NH615 BCM4329. Wi-Fi should work out of the box. All needed stuff is included.
Y Bluetooth Uses Azurewave AW-NH615 BCM4329B1. Works fine out of the box.
Y GPIO keys There are 3 keys on GPIO: Power, Volume up, Volume down.

Additionally GPIO-keys like are LID sensor and Audio dock line-out detect.

Y Vibro Transformer Prime has GPIO based vibrator.
Y Dock Keyboard Both pad and dock have Nuvoton NPCE795LA0BX embedded controller which handles battery data, charging, leds, keyboard and touchpad. Driver of this EC is mainlined and is fully functional. Keyboard and Touchpad work.

Alt Gr can be used for alternate multimedia keys instead of escape, fn keys, volumes and delete. Alt GR + Lock changes the default key mode.

Y Battery/Charger Driver is based on Texas Instruments bq24725 SMBus Charge Controller driver and GPIO charger but works through pad/dock EC. Charging and charge level of both batteries are shown correctly.
Y PMIC Transformers use Texas Instruments TPS659110 PMIC and TPS62361 core regulator.
P Sound Sound codec is RT5631. Sound works only if boot from downstream kexec. Reason unknown. Audio via HDMI works out of the box.
N Voice processor Transformers use separate Fortemedia FM34NE voice processor. Mainline driver prototype is available but kernel lacks way to get mic status (dsp is internal mic dependent). Is used for voice processing and cancelling. Currently is disabled.
Y Thermal sensor NCT1008 ON Semiconductor LM90 series thermometer.
Y Orientation sensors Include Invensense mpu3050 gyroscope with Kionix KXTF9 accelerometer and Aichi AMI306 3-axis digital compass.
Y Light sensor Driver Dyna-Image AL3010. Brightness regulation works, install iio-sensor-proxy . It's slightly oversensitive.
N Front camera Aptina mi1040 camera sensor. Grate kernel doesn't support VI yet.
N Rear camera Fujitsu MBG048 image processor. Since it is broken on most TF201 is not planned to be added to support list. If you have such a need, development is welcome. Mainline driver doesn't exist.
P ULP GeForce GPU Acceleration partially works.

Participate development


  • sound needs further investigations, issue is common for all transformers;
  • emmc vio voltage is 3.3v when proper should be 1.8v (setting 1.8v brakes emmc); MicroSD vdd supply is always on and MicroSD frequency is limited - all 3 are ASUS bootloader bugs, u-boot does not have this bugs;
  • BCM4751 GPS is commonly used in devices of this age, although it still does not have proper implementation (nor kernel, nor userspace);
  • Fortemedia fm34ne has driver prototype, but kernel lacks way to get audio devices state (dsp is used only for internal mic). Driver probe fails, maybe connected with sound issue.


  • fastboot aliases are broken
  • legacy android boot.img stuck when loaded via u-boot (u-boot can not establish trustzone)


Desktop environment

Since 3D acceleration is not available yet, all DE which use it will be painfully slow and laggy.

Currently xfce4 or mate are recommended.


Note Further procedure needs pre-made nvflash. Files blob.bin and bricksave.img are only thing that will save you from full brick and allow replace/restore Asus bootloader.

Current U-Boot status on Asus Transformer Prime TF201

Status Feature Info
Y Boot itself U-Boot successfully boots when is flashed into EBT partition instead of Asus bootloader. Can be additionally booted via fusée gelée exploit, even in locked state.
Y Panel Boot process is shown on panel.
Y MicroSD Fully functional and detectable. Can be used as boot source.
Y eMMC Mostly functional and detectable. Can be used as boot source.
Y Boot kernel Yes, by default kernel and dtb are booted from 1st partition on sdcard, if nothing found, u-boot will check /system partition of eMMC. Kernel name must be vmlinuz, dtb - tegra30-asus-tf201.dtb, ramdisk is optional, name is uInitrd and it must be in u-boot format.
Y Boot menu Native u-boot bootmenu works perfectly fine. It can be called with pressing volume down button on boot.
Y Power management Offline charging and charging in u-boot both work and are hw configured. Both power off and reboot options work and are available in bootmenu. If no valid kernel is found tablet will turn off.
P Fastboot Fastboot option is available in bootmenu. All functions but flash/erase/reboot-bootloader operate correctly.
Y Bricksafe hook U-Boot can successfully generate and restore device specific image of first 3 encrypted partitions. It is identical to one, generated with nvflash command. If you can not perform nvflash, use fusée gelée to launch u-boot from RAM and generate bricksafe. You need to insert blank fat microSD so it can be saved!
Y Boot from script Boot from script option allows to load boot configuration from uboot-transformer.bcs - a text file, located in a small fat partition on eMMC (mmcblk0p5 or PER).
P Boot Android Booting both Android kernel (LNX) and Recovery (SOS) are implemented. Legacy kernel requires Trusted Zone, which is not supported by u-boot. FIX ME!
P Self update Self update option is implemented and write is done correctly. HOWEVER, for encryption/decryption device specific AES key is required and currently there is no way to get it from u-boot. Currently disabled. FIX ME (implement Tegra SE?)!

Primary, you need to build a u-boot from this source (github) on master branch and transformer_t30_defconfig tf201.config. Use same GCC as for kernel. When build is finished, you will get a file with name u-boot-dtb-tegra.bin. This is new bootloader.

Next, rebuild dtb from this branch. Additionally, if initramfs is used, you must convert it into u-boot format.

Last step is flashing new bootloader. Place previously built u-boot-dtb-tegra.bin into your nvflash folder. Put prepared microSD into tablet. Set your device into APX mode and perform

1 sudo ./wheelie --blob blob.bin
2 sudo ./nvflash --resume --download 4 u-boot-dtb-tegra.bin

And wait till tablet boots.

If you need to restore Asus bootloader, you can find one in stock firmware blob and flash it with same method.

Boot from script

Script is a text file, named uboot-transformer.bcs and placed into PER partition (mmcblk0p5 the only fat partition on eMMC).

This is file content example:

 1 # TF201 u-boot configuration
 3 # Kernel cmd line
 4 bootargs=console=tty0,115200n8 root=/dev/mmcblk1p2 rw gpt
 6 # Target file names
 7 dtb_file=tegra30-asus-tf201.dtb
 8 kernel_file=vmlinuz
 9 ramdisk_file=uInitrd
11 fs_type=fatload # partition format
12 dev_type=mmc # device type, may be mmc, usb etc
13 mmcdev=1 # number of device, like here mmcblk(0)p1 in brackets 
14 mmcpart=1 # partition number, like here mmcblk0p(1) in brackets

Everything in italics apart first line is for description and must be removed in final file.

Serial console

Asus Transformers have serial port both on motherboard and in 40 pin connector.


J0801 setup. Clickable

On motherboard serial console can be organized via J0801 according to enclosed scheme. UART is UART-A (serial@70006000; 115200n8) and uses 3.3v. This method requires disassembling tablet.


Serial console can be additionally made from standard charging cable, but in process cable will be destroyed.

You would need:

- Asus charging cable;

- UART to USB (like CP2102);

- 3 wires with pin plugs on end;

- Soldering iron, a bit of skill;

UART place in 40pin plug

First of all you need to cut both ends of charging cable and prepare any 3 of cable wires for further soldering on both sides. Then solder your wires with pin plugs to prepared wires of Asus cable on ONE SIDE.

Now we need to prepare 40 pin plug. It's cover is solid, but there is a plastic rubber around metal plug, it needs to be cut, then metal plug can be carefully extracted. Controller board is covered with black silicon, it needs to be teared as well. Then you need to unsolder ground (black wire), it holds board to metal plug. After board can be unsoldered or gently pulled and it will come out with pins. Then you have to remove all remaining pins, find where 6 and 7 pins are on shorter side (!) and make their holes a bit bigger (holes from board side!). Insert pins from board(I've inserted mine with 90°, they insert easier and work fine; additionally you may try straightened stapler clip). Now you can solder wires on other side of Asus cable to pins and to metal connector. Additionally, I have fixed pins with super glue, before fixing pins check is they reach almost end of its groove.

6th pin is RX of device and 7th pin is TX of device, GND is on metal connector.

Connect RX (6th pin wire) to TX of CP2102, TX (7th pin wire) to RX of CP2102 and GND to GND respectively. Plug your USB adapter, configure it and you are ready to take UART logs.

40pin plug
UART cable

See also