User manual

Note that the levels at board's UART0 are in CMOS level (3.3V) and you would need a MAX232

convertor to bring them to TTL one! That is true for the RX and TX also! You would need to

consider that if you decide to make your own cable.

The cable probably needs drivers – after successful driver installation a COM port device would

show up in the hardware manager of your computer. Then you would need to connect the serial

cable wires to the board as follows: RX line to UART1-TX pin; TX line to UART1-RX pin; GND

to GND. The last pin of UART1 connector is named 3.3V and it can be used to power the board, if

you have other ways of power the board leave 3.3V pin unconnected! Be careful to avoid the

connection to the serial cable else there would be a short-circuit. Make sure that the serial cable is

connected to your personal computer and recognized properly after driver installation.

Then open a terminal program on the serial (COM) port which the cable is associated with. The

settings for the connection are 115200 baud, 8-N-1. After everything else is set, you would need to

power the board as explained in “2.3 Powering the board”.

2.5.2 HDMI monitor

The board comes equipped with HDMI connector to connect to a compatible monitor. However,

there is no cable included. Make sure to use a tested HMDI cable.

All official Debian and Android images for A20-OLinuXino-LIME2 have HDMI output enabled by

default. The board should work out-of-the-box with a native HDMI monitor.

The default HDMI resolution in the official images is 720p60 (1280×720p at 60Hz). In order to

change that setting the video output on the LCD display you would need to run a configuration

script (if you use Debian Linux) or download a suitable image (if you use Android). Video output

settings are hard-coded in Android images but there are ways to edit the images. You might more

information about editing pre-built Android images at this wiki article: how to edit prebuilt Android

images.

More information about the video output settings and the usage of video settings script might be

found in chapter “2.6 Changing the default image resolution”.

2.5.3 LCD display

Various LCD displays can be attached to A20-OLinuXino-LIME2 and used to interact with the

board.

Depending on the display chosen and whether you attempt to run Debian Linux or Android

additional video settings configuration may be required. It is always a good idea to have one of the

other connection options available as back-up (in case the video output settings need modification).

For more information refer to chapter “2.7 Connecting and calibrating a display”.

2.5.4 SSH via mini USB cable in Debian

The latest official Debian Linux image allows the use the USB_OTG connector for SSH connection

without the need of a LAN cable or a serial cable. You can use a mini USB cable connected

between your host PC and the on-board mini USB connector. For connection convenience there is a

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