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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

Summary of Contents for A20-OLINUXINO-LIME2

Page 1: ...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 ...

Page 2: ...urpose 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...

Page 3: ...tor 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 Introd...

Page 4: ...rpose 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 SUPP...

Page 5: ... 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 ...

Page 6: ...the board The base version of the board that comes with NO extra flash memory is named A20 OLinuXino LIME2 These three variants with extra flash memory are named A20 OLinuXino LIME2 e4GB A20 OLinuXino n4GB and A20 OLinuXino LIME2 n8GB The name consists of the type of the memory and the size of the memory suffix e4GB stands for eMMC type of flash with 4GB of size n4GB stands for NAND type of flash ...

Page 7: ...g Due to the hardware differences listed above the Linux and Android distributions of the LIME2 and LIME boards are not identical Furthermore some of the hardware extensions are not compatible with both of the designs For example the A10 OLINUXINO LIME UEXT is not compatible with A20 OLinuXino LIME2 board 1 4 Board version used in the manual Revision B boards and resources were used while writing ...

Page 8: ...tware notes Chapter 3 contains the general board diagram and layout Chapter 4 describes the component that is the heart of the board the A20 Allwinner processor Chapter 5 is an explanation of the control circuitry associated with the processor Chapter 6 covers the connector pinout peripherals and jumper description Chapter 7 provides the schematics and the dimensions of the board Chapter 8 contain...

Page 9: ...ect an HDMI cable between a TV and the board it is a good idea to have them both connected to the same electrical source to the same utility power socket This might be said for a serial cable connected between a PC and the board s DEBUG port In rare cases different polarity might cause hardware damage to the board 2 2 Requirements In order to set up the A20 OLinuXino LIME2 optimally one or more ad...

Page 10: ...nuXino LIME A20 LIME ANDROID SD a tested class 10 micro SD card with the latest by the time of leaving the Olimex facilities official Android release A20 LIME DEBIAN SD a tested class 10 micro SD card with the latest by the time of leaving Olimex facilities official Debian Linux release USB SERIAL CABLE F female USB serial console cable USB MINI CABLE standard USB type A to USB type mini cable A20...

Page 11: ...from the USB_OTG the current provided might be insufficient to also power a bigger LCD connected to the LCD_con However this power option is capable of driving the board when using external display connected to the HDMI connector The typical consumption of A20 OLinuXino LIME2 is between 400mA and 650mA depending on the current load If the board has entered power down state you can bring it back wi...

Page 12: ... on each of the connections might be found in the consequent sub chapters Note that not all interface options are available for all images Furthermore some of the ways of interaction are obviously not suitable for Android OS The official Debian image should give you the most possible options of interfacing the board Using HDMI LCD_CON or LAN might require additional configurations Furthermore it i...

Page 13: ... settings are hard coded in Android images but there are ways to edit the images You might find 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 displ...

Page 14: ...ser would not need to edit the files however To ease the process of changing the resolution we have compiled a number of Android images for the Android users with hard coded video output settings Alternatively for Debian Linux users we have provided a shell script that can be executed in order to set preferred video output and resolution For Android that you boot from the NAND memory you would nee...

Page 15: ...s no VGA connector and you would need to install additional hardware more instructions on the VGA signals might be found in the chapter 6 0 1680 1050 1 1440 900 2 1360 768 3 1280 1024 4 1024 768 5 800 600 6 640 480 7 1920 1080 8 1280 720 Chose the resolution that suits you and reboot the board If you decide to edit the configurations yourself the easiest way would be to do it on the board This can...

Page 16: ...boot script fex boot script bin Finally reboot the board reboot Reboot the board and the new settings would be applied Alternatively you can do the changes on the microSD card off the board You would need to remove the microSD card and explore it in a microSD card reader You would need to edit the configuration file script bin and edit the settings inside This file is usually located in Script bin...

Page 17: ... step connectors Product page CABLE 40 40 10CM 10cm long cable suitable for 0 05 step connectors Product page The displays recommended for the board at the moment of writing might be found in the following table Display name Size of display in inches Native resolution in pixels Official Debian image support Official Android image support Link to product page LCD OlinuXino 4 3TS 4 3 480 272 Yes No ...

Page 18: ... the password olimex calibrate the touch screen and reboot the board sudo reboot 2 8 GPIO under Debian You can read data from a given GPIO port The logical ranges are usually as follows 0V 1V for LOW or 0 2 4V 3 3V for HIGH or 1 All voltages are measured against ground GND If the input signal is to high you will at least destroy the port The algorithms for writing a value to a GPIO port and readin...

Page 19: ... are featured at the wiki article of the device https www olimex com wiki A20 OLinuXino LIME2 We usually try to provide details on how to build the Linux and the Android images at our GitHib page https github com OLIMEX OLINUXINO tree master SOFTWARE A20 Another useful place is the Olimex forums where a lot of people share their experience and advice https www olimex com forum The official images ...

Page 20: ...inuXino LIME2 user s manual more information However we won t install a piece of software for you or write custom program for you We won t provide a specific software solution to a specific software problem Page 20 of 51 ...

Page 21: ... you get acquainted with the main parts of the board Note the names used on the board might differ from the names used below to describe them For the actual names check the A20 OLinuXino LIME2 board itself 3 1 Layout top view The picture below shows the top side of the board and highlights the most important parts Page 21 of 51 ...

Page 22: ...OLIMEX 2017 A20 OLinuXino LIME2 user s manual 3 2 Layout bottom view At the bottom are located mainly the buttons and microSD card connector Page 22 of 51 ...

Page 23: ...n Jpeg Mjpeg etc H 264 High Profile 1080p 30fps or 720p 60fps encoding 3840 1080 30fps 3D decoding BD SBS TAB FP supported Complies with RTSP HTTP HLS RTMP MMS streaming media protocols DISPLAY Supports multi channel HD display Integrated HDMI 1 4 transmitter with HDCP support CPU RGB LVDS LCD interface Supports CVBS YPbPr VGA Integrated TV decoder CAMERA Integrated parallel 8 bit I F YUV sensor I...

Page 24: ...OLIMEX 2017 A20 OLinuXino LIME2 user s manual 4 2 Block diagram The block diagram is taken from Allwinner s web site Page 24 of 51 ...

Page 25: ...rystal Q3 is found at pins N22 and N23 of the A20 microcontroller 5 3 Power supply circuit The power supply is handled mainly by AXP209 power management system an Allwinner chip that goes together with the A20 processor It is mounted on the board but since it is relatively hard to find we also sell it separately The power supply circuit of A20 OLinuXino LIME2 requires input supply of 5V The minimu...

Page 26: ...e RX line of the target board The BLUE wire should go to the target s GND line UART0 Pin Signal name Processor pin 1 UART0 TX A7 2 UART0 RX B7 3 GND POWER CIRCUIT 6 2 MicroSD card connector The micro SD card slot is primarily used for booting the operating system The board works with micro SDHC cards up to 32GB of storage As a general precaution be careful with the SD cards you purchase There is a...

Page 27: ...e Class 10 10MByte sec card for faster read write operations lower class cards especially higher capacity ones might slow down the whole system SD MMC connector Pin Connector signal name Wire name processor pin 1 DAT2 RES SD0 D2 K19 2 CD DAT3 CS SD0 D3 K20 3 CMD DI SD0 CMD L19 4 VDD POWER CIRCUIT 5 CLK SCLK SD0 CLK L20 6 VSS2 POWER CIRCUIT 7 DAT0 DO SD0 D0 M19 8 DAT1 RES SD0 D1 M20 Additionally th...

Page 28: ...e image located on the NAND of A20 OLinuXino LIME2 4GB is via the USB OTG connector the update of the Android image is explained at the bottom of this sub chapter The connector can also be used for establishing SSH connection to the default Debian Linux of LIME2 boards for more information about the tethering please refer to 2 5 4 SSH via mini USB cable in Debian The part of the schematic related ...

Page 29: ...ve linked A20 wiki article To repair the image on NAND re upload it following these easy steps 1 Install and run PhoenixSuit can be found in the wiki article of the board 2 Go to firmware tab of the program and point to a valid Android image the latest official one may also be downloaded from the wiki article 3 Disconnect the power supply and USB cable from the A20 board 4 Press and hold RECOVERY ...

Page 30: ...you have plugged to the board try to draw more current than 523mA combined The maximum current available on each of the USB hosts is exactly 523mA The SY6280 responsible for the USB_HOST1 is enabled by USB0 DRV1 processor pin A4 The SY6280 responsible for the USB_HOST2 is enabled by USB0 DRV2 processor pin A5 USB_HOST connectors USB_HOST1 Signal name Processor pin USB_HOST2 Signal name Processor p...

Page 31: ...CP you need to enable auto detection and dhcp as shown below auto eth0 iface eth0 inet dhcp For setting a static address please follow the pattern below auto eth0 iface eth0 inet static address 192 168 1 5 netmask 255 255 255 0 gateway 192 168 1 254 The EEPROM memory may be used to store the MAC address Important In some Debian images it is possible that the Ethernet doesn t get auto detected duri...

Page 32: ...to set the appropriate HDMI output HDMI connector Pin Signal name Processor pin Pin Signal name Processor pin 1 HTX2P T23 11 GND POWER CIRCUIT 2 GND POWER CIRCUIT 12 HTXCN W22 3 HTX2N T22 13 HCEC P23 4 HTX1P U23 14 NA NA 5 GND POWER CIRCUIT 15 HSCL R23 6 HTX1N U22 16 HSDA R22 7 HTX0P U23 17 GND POWER CIRCUIT 8 GND POWER CIRCUIT 18 5V POWER CIRCUIT 9 HTX0N U22 19 HHPD P22 10 HTXCP W23 Pin 14 of the...

Page 33: ...ormation please visit https www olimex com Products Components Cables SATA CABLE SET Pay note the two jumpers 5V_E_SATA and PC3 PB8 located at the bottom of the board under the HDMI connector The first one 5V_E_SATA is open by default because the board has software control of the powering for the hard disk If you close 5V_E_SATA there would always be 5V at the 5V_SATA_PWR connector Which pin does ...

Page 34: ... note that part of the VGA and composite video signals are multiplexed VGA R VGA B VGA G share the same pins with the TVOUT signals Composite video signals are located on GPIO 1 connector TVOUT0 GPIO 1 pin 20 TVOUT1 GPIO 1 pin 22 TVOUT2 GPIO 1 pin 24 you would also need AGND GPIO 1 pin 4 VGA signals are located at GPIO 1 connector and LCD_CON connector The total of 5 signals you need for VGA outpu...

Page 35: ...0VGA G AC16 21PG8 D19 22VGA B AB16 23PG9 C19 24VGA R AC17 25PG10 D18 26UART0 RX B7 27PG11 C18 28UART0 TX A7 29PC3 SATA PWR EN L22 30PB21 C7 31PC18 F22 32PB20 C8 33PC19 L21 34PB19 B8 35PC20 K21 36PB18 A8 37PC21 J21 38PC24 F21 39PC22 J20 40PC23 G19 Signals marked with are multiplexed with either a peripheral device or another connector Ensure that the multiplexing is handled properly on software and...

Page 36: ...3_2 8V Goes to AXP209 5 TWI0 SCK A15 6 PE0 E23 7 TWI0 SDA B15 8 PE1 E22 9 PI0 A20 10 PE2 D23 11 PI1 B20 12 PE3 D22 13 PI2 A19 14 PE4 C23 15 PI3 B19 16 PE5 C22 17 PI4 A18 18 PE6 B23 19 PI5 B18 20 PE7 B22 21 PI6 A17 22 PE8 A23 23 PI7 B17 24 PE9 A22 25 PI8 A16 26 PE10 B21 27 PI9 B16 28 PE11 A21 29 PI10 A15 30 PI21 E13 31 PI11 B15 32 PI20 E14 33 PI12 A14 34 PI19 D14 35 PI13 B14 36 PI18 E15 37 PI14 A13...

Page 37: ...2 E1 38 PH26 F3 39 PH23 E2 40 PH27 F4 6 9 4 GPIO 4 General Purpose Input Output 20pin connector GPIO 4 connector features the rest of the signals available and few additional signals that might need testing GPIO 4 connector Pin Signal name Processor pin Pin Signal name Processor pin 1 3 3V POWER CIRCUIT 2 GND POWER CIRCUIT 3 TVOUT3 AB17 4 NMI_N F5 5 TVIN0 AC18 6 MIC1OUTP AC22 7 TVIN1 AB18 8 MIC1OU...

Page 38: ...to A20 OLinuXino LIME and A10 OLinuXino LIME Please note that the smallest display 4 3 480 272 is not suitable for the official Android images we provide LCD_CON connector Pin Signal name Processor pin Pin Signal name Processor pin 1 5V POWER CIRCUIT 2 GND POWER CIRCUIT 3 3 3V POWER CIRCUIT 4 GND POWER CIRCUIT 5 LCD_D16 Y12 6 LCD_D17 AA12 7 LCD_D18 Y11 8 LCD_D19 AA11 9 LCD_D20 Y10 10 LCD_D21 AA20 ...

Page 39: ...x com wiki A20 OLinuXino LIME2 using an operating system NAND flash In Debian Linux you would need to start a start a shell script to change the built in the image resolution settings Start it with change_display_a20_olimex sh and follow the instructions Please refer to chapter 2 6 Changing the default image resolution for more information Page 39 of 51 ...

Page 40: ... is port PC3 Changing this jumper also changes the availability of PC3 and PB8 at GPIO 1 pin 29 and GPIO 3 pin 16 Please note that if you change the position of the jumper from PC3 to PB8 then you might block one of the processor pins responsible for I2S and AC97 audio output PB9 PH7_USB SMT PB9 Controls which processor pin should be used for the USB_OTG By default the USB_OTG uses processor pin C...

Page 41: ...e value that we use in our default images is 384 just in case somebody uses the board in environments with higher than typical ambient temperature or in applications that stress the memories all the time If you wish to change the clock of the RAM memory you need to rebuild the u boot as per our instructions and either set higher clock speed in the MENUCONFIG or directly change the value of the CON...

Page 42: ...ing a GitHub account We mostly use Eagle by Cad Soft 4 16r2 for designing However the files should be compatible with the latest Eagle available Cad Soft offers a trial version of their software that allows you to inspect schematics and board files without being able to modify them This work is licensed under the Creative Commons Attribution ShareAlike 3 0 Unported License To view a copy of this l...

Page 43: ...OLIMEX 2017 A20 OLinuXino LIME2 user s manual 7 2 Physical dimensions Note that all dimensions are in mils Page 43 of 51 ...

Page 44: ...3 memory according to the latest schematic 31 40 C 30 11 15 Made it more obvious that there are differences in the layout of LIME2 and LIME connector board layout Clarified that the 4GB version of the board is now sold without Android Updated hardware board revision changes 33 37 5 6 43 D 23 12 15 Clarified that we no longer load Android on the 4GB version of the board Added information about Debi...

Page 45: ...icro connected to GND odd milling shape changed to rectangular 2 R109 change from 47k 0402 to 470k 0402 R107 changed from 470k 0402 to capacitor 220nF 0402 because new PHY consumes too much current at startup 8 3 Useful web links and purchase codes The web page you can visit for more information about your device are Product page https www olimex com Products OLinuXino A20 A20 OLinuXino LIME2 Wiki...

Page 46: ...480 LCD OLINUXINO 10TS low cost 10 LCD display with optional touchscreen component 1024 600 LCD OLINUXINO 15 6 low cost 15 6 LCD display 1366 768 LCD OLINUXINO 15 6FHD low cost Full HD 15 6 LCD display 1920 1080 CABLE IDC40 15cm cable for LCD to LCD_CON connection SATA HDD 2 5 500GB 500GB 2 5 SATA hard disk SATA CABLE SET cables that allow the connection of a 2 5 hard disk to the board ALUMINIUM H...

Page 47: ...ommercial temperature range 0 70C Q How long this board will be available A This board will be available forever Q I use LCD_CON for video output There is some screen flickering under Debian What could be the reason A This is usually caused by either a loose cable connection or badly configured script bin Double check if all cables are properly connected Also check if there is a change in the beha...

Page 48: ...SD card is either the native Android image that can be downloaded to the card via a software tool like PhoenixSuit through the board or an image taken from an already prepared microSD card that requires to simply write the image through a microSD card reader It is more likely that you have an Android image that requires a simple copy to a card If that is the case you can follow the exact steps as ...

Page 49: ...e Q How to edit board configurations and definitions in the official Android images A There is a wiki article about that please visit wiki article Q Is it possible to boot Debian from NAND Do you provide such image A Yes it is possible Use the latest Debian Jessie image and write nandinstall If there are problems try to upload Android first to the NAND and then try nandinstall again More informati...

Page 50: ...els are headless no audio or video output are supported If you don t need audio or video go for it it had been tested and confirmed working there are installation reports even here https wiki debian org InstallingDebianOn Allwinner Q I have a 4GB version of the board The board doesn t seem to have Android loaded A We no longer load Android on the NAND memory of the boards You can upload Android fo...

Page 51: ...orrect ordered items are allowed subject to a 10 restocking fee What is unaffected If you hooked it to power you affected it To be clear this includes items that have been soldered to or have had their firmware changed Because of the nature of the products we deal with prototyping electronic tools we cannot allow returns of items that have been programmed powered up or otherwise changed post shipm...

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