A20-OLINUXINO-LIME2
and
A20-OLINUXINO-LIME2-4GB
Open-source single-board Android/Linux mini-computer
USER’S MANUAL
Document revision G, September 2017
Designed by OLIMEX Ltd, 2014
All boards produced by Olimex LTD are ROHS compliant
OLIMEX© 2017
A20-OLinuXino-LIME2 user's manual
DISCLAIMER
© 2017 Olimex Ltd. Olimex®, logo and combinations thereof, are registered trademarks of Olimex Ltd. Other product
names may be trademarks of others and the rights belong to their respective owners.
The information in this document is provided in connection with Olimex products. No license, express or implied
or otherwise, to any intellectual property right is granted by this document or in connection with the sale of
Olimex products.
This work is licensed under the Creative Commons Attribution-ShareAlike 3.0 Unported License. To view a copy of
this license, visit
http://www.creativecommons.org/licenses/by-sa/3.0/.
This hardware design by Olimex LTD is licensed under a Creative Commons Attribution-ShareAlike 3.0 Unported
License.
The software is released under GPL.
It is possible that the pictures in this manual differ from the latest revision of the board.
The product described in this document is subject to continuous development and improvements. All particulars of the
product and its use contained in this document are given by OLIMEX in good faith. However all warranties implied or
expressed including but not limited to implied warranties of merchantability or fitness for purpose are excluded. This
document is intended only to assist the reader in the use of the product. OLIMEX Ltd. shall not be liable for any loss or
damage arising from the use of any information in this document or any error or omission in such information or any
incorrect use of the product.
This evaluation board/kit is intended for use for engineering development, demonstration, or evaluation purposes only
and is not considered by OLIMEX to be a finished end-product fit for general consumer use. Persons handling the
product must have electronics training and observe good engineering practice standards. As such, the goods being
provided are not intended to be complete in terms of required design-, marketing-, and/or manufacturing-related
protective considerations, including product safety and environmental measures typically found in end products that
incorporate such semiconductor components or circuit boards.
Olimex currently deals with a variety of customers for products, and therefore our arrangement with the user is not
exclusive. Olimex assumes no liability for applications assistance, customer product design, software performance, or
infringement of patents or services described herein.
THERE IS NO WARRANTY FOR THE DESIGN MATERIALS AND THE COMPONENTS
USED TO CREATE A20-OLINUXINO-LIME2 AND A20-OLINUXINO-LIME2-4GB. THEY
ARE CONSIDERED SUITABLE ONLY FOR, RESPECTIVELY, A20-OLINUXINO-LIME2
OR A20-OLINUXINO-LIME2-4GB.
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OLIMEX© 2017
A20-OLinuXino-LIME2 user's manual
Table of Contents
DISCLAIMER......................................................................................................................................2
CHAPTER 1: OVERVIEW..................................................................................................................5
1. Introduction to the chapter...........................................................................................................5
1.1 Features......................................................................................................................................5
1.2 Target market and purpose of the board.....................................................................................6
1.3 Board variants............................................................................................................................6
1.4 Board version used in the manual..............................................................................................7
1.5 Document organization..............................................................................................................8
CHAPTER 2: SETTING UP THE OLINUXINO BOARD.................................................................9
2. Introduction to the chapter...........................................................................................................9
2.1 Electrostatic and electrical polarity warning............................................................................. 9
2.2 Requirements............................................................................................................................. 9
2.3 Powering the board.................................................................................................................. 11
2.4 Button functions.......................................................................................................................12
2.5 Interacting with the board........................................................................................................12
2.5.1 Serial connection at UART0...........................................................................................................................12
2.5.2 HDMI monitor................................................................................................................................................13
2.5.3 LCD display................................................................................................................................................... 13
2.5.4 SSH via mini USB cable in Debian................................................................................................................13
2.5.5 SSH via Ethernet connector...........................................................................................................................14
2.6 Changing the default video output resolution..........................................................................14
2.7 Connecting and calibrating a display.......................................................................................17
2.7.1 Android calibration.........................................................................................................................................17
2.7.2 Debian calibration..........................................................................................................................................18
2.8 GPIO under Debian................................................................................................................. 18
2.9 I2C and SPI under Debian....................................................................................................... 19
2.10 Software support....................................................................................................................19
CHAPTER 3: A20-OLINUXINO-LIME2 BOARD DESCRIPTION............................................... 21
3. Introduction to the chapter.........................................................................................................21
3.1 Layout (top view).....................................................................................................................21
3.2 Layout (bottom view).............................................................................................................. 22
CHAPTER 4: THE ALLWINNER A20 MICROCONTROLLER.....................................................23
4. Introduction to the chapter.........................................................................................................23
4.1 The processor...........................................................................................................................23
4.2 Block diagram..........................................................................................................................24
CHAPTER 5: CONTROL CIRCUITY.............................................................................................. 25
5. Introduction to the chapter.........................................................................................................25
5.1 Reset.........................................................................................................................................25
5.2 Clocks...................................................................................................................................... 25
5.3 Power supply circuit................................................................................................................ 25
CHAPTER 6: CONNECTORS AND PINOUT.................................................................................26
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OLIMEX© 2017
A20-OLinuXino-LIME2 user's manual
6. Introduction to the chapter.........................................................................................................26
6.1 UART0 interface......................................................................................................................26
6.2 MicroSD card connector..........................................................................................................26
6.2.1 SD/MMC1 slot...............................................................................................................................................26
6.3 PWR jack.................................................................................................................................28
6.4 USB_OTG............................................................................................................................... 28
6.5 USB_HOST connectors...........................................................................................................30
6.6 Gigabit Ethernet.......................................................................................................................31
6.7 HDMI connector......................................................................................................................32
6.8 SATA connector and power..................................................................................................... 33
6.9 GPIO connectors......................................................................................................................33
6.9.1 GPIO-1 (General Purpose Input/Output) 40pin connector.............................................................................34
6.9.2 GPIO-2 (General Purpose Input/Output) 40pin connector.............................................................................36
6.9.3 GPIO-3 (General Purpose Input/Output) 40pin connector.............................................................................37
6.9.4 GPIO-4 (General Purpose Input/Output) 20pin connector.............................................................................37
6.10 LCD_CON 40pin connector..................................................................................................38
6.11 Jumper description.................................................................................................................40
6.12 Additional hardware components.......................................................................................... 41
CHAPTER 7: SCHEMATICS............................................................................................................42
7. Introduction to the chapter.........................................................................................................42
7.1 Eagle schematic....................................................................................................................... 42
7.2 Physical dimensions.................................................................................................................43
CHAPTER 8: REVISION HISTORY AND SUPPORT.................................................................... 44
8. Introduction to the chapter.........................................................................................................44
8.1 Document revision...................................................................................................................44
8.2 Board revision..........................................................................................................................45
8.3 Useful web links and purchase codes......................................................................................45
8.4 Frequently asked questions......................................................................................................47
8.5 Product support........................................................................................................................51
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OLIMEX© 2017
A20-OLinuXino-LIME2 user's manual
CHAPTER 1: OVERVIEW
1. Introduction to the chapter
Thank you for choosing this OLinuXino single board computer from Olimex! This document provides a
user’s guide for the Olimex A20-OLinuXino-LIME2 board. As an overview, this chapter gives the scope
of this document and lists the board’s features. The document’s organization is then detailed.
The A20-OLinuXino-LIME2 development board enables code development of applications running on
the A20 microcontroller, manufactured by Allwinner Technology from China.
OLinuXino is an open-source, open-hardware project and all design files are available to the customer.
1.1 Features
The board has the following set of features:
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A20 Cortex-A7 dual-core ARM Cortex-A7 CPU and dual-core Mali 400 GPU
1GB DDR3 RAM memory
1000MBit native Ethernet
4GB or 8GB NAND FLASH memory (available only on certain variants of the board)
4GB eMMC memory (available only on certain variants of the board)
SATA connector with 5V SATA power jack
Native HDMI interface with standard connector
Capable of FullHD (1080p) video playback
2x USB Low-Full-High-Speed hosts with power control and current limiter
USB-OTG with power control and current limiter
LiPo Battery connector with battery-charging capabilities
LCD row of pins (0.05'' step)
160 GPIOs on four GPIO rows of pins (0.05'' step)
MicroSD card connector
DEBUG-UART connector for console debug with USB-SERIAL-CABLE-F
Status LED
Battery charge status LED
Power LED
2KB EEPROM for MAC address storage and more
2 BUTTONS with ANDROID functionality + RESET button
2 mount holes
5V input power supply, noise immune design
PCB dimensions: (84 × 60)mm ~ (3.3 × 2.4)"
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