Official Images from OLIMEX
Note only microSD card will boot, SD-MMC card on the back will not boot as not part of boot sequence (reffer to A20 datasheet).
A20 Debian 4GB SD-card image release-3 with:
- Linux Kernel 3.4.43+
- XFCE4 desktop environment
- Mplayer CLI
- GCC 4.6
- 4.3"(480x272), 7"(800x480) and 10" (1024x600) LCD and touchscreen support
- USB WIFI RTL8188CU, Ethernet AX88772B
- Audio (MIC and Headphones)
- Python 2.7
- A13-LCD 4.3″TS 4.3″ LCD with backlight and touchscreen 480×272 pixels
- A13-LCD7″TS 7″ LCD with backlight and touchscreen 800×480 pixels
- A10-LCD10″TS 10.1″ LCD with backlight and touchscreen 1024×600 pixels
- Micro SD card
- SD/MMC card
- OTG USB
- HIGH SPEED HOST1 USB
- HIGH SPEED HOST2 USB
- ETHERNET 100MBIT
- Audio IN
- Audio OUT
- Default Login: root/olimex
Note: the A20-Debian-SD card which we have on our webshop contain same image on 4GB Class10 fast micro sd-card, if you want to use this image please use Class10 fast card or the performance of Linux will slow down
Latest A20-OLinuXino-MICRO Android NAND image revision 2 (The LAN and the bottom SD card should be working properly now. Note that there are at least 2 things NOT working as intended in this Android release: 1. The touch screen support; 2. The bottom USB_HOST connector. It is being worked on fixing these problems!)
Older A20-OLinuXino-MICRO preliminary Android NAND image (Note that there are at least 4 things NOT working as intended in this Android release: 1. The Ethernet; 2. The bottom SD card; 3. The touch screen support; 4. The bottom USB_HOST connector. It is being worked on fixing these problems!)
A20-SDK 2.0 for building Android images
obsolete A20-SDK torrent for building Android images just for reference, the early version of Android image was built with this SDK
A20 Users Manual
A20 Users manual
A20-OLinuXino-MICRO and A20-OLinuXino-MICRO-4GB basic dimensions in mils: image in PNG format
In order to use A20 GPIO's first you have to export them. For example:
root@A20:~# for i in `seq 1 1 230`; do echo $i > /sys/class/gpio/export; done
list of all available GPIO
root@A20:~# ls /sys/class/gpio/
export gpio21_pc3/ gpio33_pb8/ gpio45_ph27/ gpio57_ph17/ gpio69_pg5/
gpio10_pe9/ gpio22_pc7/ gpio34_pb10/ gpio46_ph0/ gpio58_ph18/ gpio6_pe5/
gpio11_pe10/ gpio23_pc16/ gpio35_pb11/ gpio47_ph2/ gpio59_ph19/ gpio70_pg6/
gpio12_pe11/ gpio24_pc17/ gpio36_pb12/ gpio48_ph7/ gpio5_pe4/ gpio71_pg7/
gpio13_pi14/ gpio25_pc18/ gpio37_pb13/ gpio49_ph9/ gpio60_ph20/ gpio72_pg8/
gpio14_pi15/ gpio26_pc23/ gpio38_pb14/ gpio4_pe3/ gpio61_ph21/ gpio73_pg9/
gpio15_pi0/ gpio27_pc24/ gpio39_pb15/ gpio50_ph10/ gpio62_ph22/ gpio74_pg10/
gpio16_pi1/ gpio28_pb3/ gpio3_pe2/ gpio51_ph11/ gpio63_ph23/ gpio75_pg11/
gpio17_pi2/ gpio29_pb4/ gpio40_pb16/ gpio52_ph12/ gpio64_pg0/ gpio7_pe6/
gpio18_pi3/ gpio2_pe1/ gpio41_pb17/ gpio53_ph13/ gpio65_pg1/ gpio8_pe7/
gpio19_pi10/ gpio30_pb5/ gpio42_ph24/ gpio54_ph14/ gpio66_pg2/ gpio9_pe8/
gpio1_pe0/ gpio31_pb6/ gpio43_ph25/ gpio55_ph15/ gpio67_pg3/ gpiochip1/
gpio20_pi11/ gpio32_pb7/ gpio44_ph26/ gpio56_ph16/ gpio68_pg4/ unexport
Example how to toggle onboard LED. The LED is connected to PH2.
root@A20:~# cd /sys/class/gpio/gpio47_ph2
make PH2 output
root@A20:/sys/class/gpio/gpio47_ph2# echo out > direction
write 1 to PH2 - LED is ON
root@A20:/sys/class/gpio/gpio47_ph2# echo 1 > value
write 0 to PH2 - LED is OFF
root@A20:/sys/class/gpio/gpio47_ph2# echo 0 > value
How to download new Android image to the NAND memory of my A20 board?
A: To repair the image on the NAND re-upload it following these steps:
- 2. Go to firmware tab of the program and point to a valid Android image (the latest official one may also be downloaded above).
- 3. Disconnect the power supply and USB cable from the A20 board.
- 4. Press and hold RECOVERY button, apply power supply (6-16)V, release RECOVERY button.
- 5. Connect USB cable to the mini USB connector.
- 6. You will be asked for drivers for the bootloader. Navigate to the folder where you extracted the PhoenixSuit and install the drivers from the respective executables (or manually point the installer to the drivers folder in the PhoenixSuit installation path).
- 7. PhoenixSuit will detect the board and would ask for the method of writing the image. Choose method of writing the image and confirm your wish to write the image.
- 8. Wait till upgrade succeeds
Note that it is not recommended to have your mini USB connected to an external USB hub. This might cause delays and might distort the signal levels. Always test with the USB connected straight to the USB ports of your computer.
How do I write the Linux image to an micro SD card to use with my A20 board?
To write a Linux image to an SD card under Windows we use Win32 Disk Imager):
- Download Win32 Disk Imager Win32 Disk Imager
- Insert card
- Start program
- Select file
- Click "write"
To write a Linux image to an SD card under Linux:
For instance you have an image with the file name of "debian_2g.img". It would be downloaded to the SD card connected to a Linux machine using one of the following commands:
- # dd bs=4M oflag=sync if=debian_2g.img of=/dev/sdX
- # cp debian_2g.img /dev/sdX
where X is the uSD card.
How to change HDMI, VGA and LCD resolutions?
The default SD card setup is made with settings for HDMI 720p/60Hz. If you want to change some other LCD, VGA or HDMI resolution then you have to start change_display.sh script file in /root directory.
and choose the resolution and the interface(LCD, HDMI or VGA).
The supported resolution are:
- 1. 4.3(480x272)
- 2. 7(800x480)
- 3. 10(1024x600)
- 0. 480i
- 1. 576i
- 2. 480p
- 3. 576p
- 4. 720p50
- 5. 720p60
- 6. 1080i50
- 7. 1080i60
- 8. 1080p24
- 9. 1080p50
- 10. 1080p60
For VGA: (note that the VGA signals are routed to custom 6 pin connector and you need from adapter to standart VGA connector)
- 0. 1680x1050
- 1. 1440x900
- 2. 1360x768
- 3. 1280x1024
- 4. 1024x768
- 5. 800x600
- 6. 640x480
- 7. 1920x1080
- 8. 1280x720