OLIMEX AM3352-SOM User Manual

AM3352-SOM

System-on-Module board capable of Linux boot

USER’S MANUAL

Document revision A, June 2015 Designed by OLIMEX Ltd, 2015

All boards produced by Olimex LTD are ROHS compliant

DISCLAIMER

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.

The hardware design of AM3352-SOM development board is considered intellectual property to Olimex. Hardware schematics are shared with the customers. However, the board layout files are considered copyright material and would not be shared.

The hardware design of AM3352-SOM-EVB development board is considered open source hardware. The source design files are published online and accessible by everyone.

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 AM3352-SOM AND AM3352-SOM-EVB. THEY ARE CONSIDERED SUITABLE ONLY FOR AM3352-SOM AND AM3352-SOM-EVB, RESPECTIVELY.

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Table of Contents

DISCLAIMER ............................................................................................................. 2

CHAPTER 1: OVERVIEW ........................................................................................ 5

1. Introduction to the chapter ....................................................................................................... 5

1.1 Introduction to SOM (System-On-a-Module) ....................................................................... 5

1.2 Target market of the board ..................................................................................................... 6

1.3 Features of AM3352-SOM ...................................................................................................... 6

1.4 Board variants .......................................................................................................................... 7

1.5 Board versions used in the manual ........................................................................................ 7

1.6 Document organization ........................................................................................................... 7

CHAPTER 2: BOARD DESCRIPTION ................................................................... 8

2. Introduction to the chapter ....................................................................................................... 8

2.1 Layout (top view) ..................................................................................................................... 8

2.2 Layout (bottom view) ............................................................................................................... 9

CHAPTER 3: SETTING UP THE AM3352-SOM BOARD .................................. 10

3. Introduction to the chapter ..................................................................................................... 10

3.1 Electrostatic and electrical polarity warnings ..................................................................... 10

3.2 Requirements .......................................................................................................................... 11

3.3 Powering the board ................................................................................................................ 12

3.3.1 Stand-alone powering ................................................................................................................................... 12

3.3.2 Mounted powering ....................................................................................................................................... 13

3.4 Button functions ..................................................................................................................... 13

3.5 Interacting with the board .................................................................................................... 14

3.6 Expanding the Debian file system space .............................................................................. 15

3.7 Changing the default image resolution ................................................................................ 15

3.8 Connecting and calibrating a display ................................................................................... 16

3.9 Software support .................................................................................................................... 17

CHAPTER 4: THE AM3352 PROCESSOR ........................................................... 18

4. Introduction to the chapter ..................................................................................................... 18

4.1 The processor ......................................................................................................................... 18

4.2 Block diagram ........................................................................................................................ 19

CHAPTER 5: CONTROL CIRCUITY ................................................................... 20

5. Introduction to the chapter ..................................................................................................... 20

5.1 Reset ........................................................................................................................................ 20

5.2 Clocks ...................................................................................................................................... 20

5.3 Power supply circuit .............................................................................................................. 20

CHAPTER 6: CONNECTORS AND PINOUT ...................................................... 21

6. Introduction to the chapter ..................................................................................................... 21

6.1 Communication with AM3352-SOM in Linux .................................................................... 21

6.2 UART0 header ....................................................................................................................... 21

6.3 MicroSD card connector ....................................................................................................... 22

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6.3.1 SD/MMC slot ................................................................................................................................................ 23

6.5 GPIO connectors .................................................................................................................... 24

6.5.1 AM_CON-GPIO1 (General Purpose Input/Output) 40pin connector .................................................... 25

6.5.2 AM_CON-GPIO2 (General Purpose Input/Output) 40pin connector .................................................... 26

6.5.3 AM_CON-GPIO3 (General Purpose Input/Output) 40pin connector .................................................... 27

6.6 AM_CON-LCD 40pin connector .......................................................................................... 28

6.7 Jumper description ................................................................................................................ 29

6.8 Additional hardware components ........................................................................................ 29

CHAPTER 7: SCHEMATICS .................................................................................. 31

7. Introduction to the chapter ..................................................................................................... 31

7.1 Eagle schematic ...................................................................................................................... 31

7.2 General physical dimensions ................................................................................................. 31

CHAPTER 8: REVISION HISTORY AND SUPPORT ........................................ 32

8. Introduction to the chapter ..................................................................................................... 32

8.1 Document revision ................................................................................................................. 32

8.2 Board revision ........................................................................................................................ 32

8.3 Useful web links ..................................................................................................................... 32

8.4 How to purchase? ................................................................................................................... 33

8.5 Order codes ............................................................................................................................. 33

8.6 Frequently asked questions ................................................................................................... 34

8.7 Product support ..................................................................................................................... 36

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CHAPTER 1: OVERVIEW

1. Introduction to the chapter

Thank you for choosing this single board computer from Olimex! This document provides a user’s guide for the AM3352-SOM 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 AM3352-SOM development board enables code development of applications running on the AM3352 microcontroller, manufactured by Texas Instruments from the U.S.A.

The AM3352-SOM board is typically used together with AM3352-SOM-EVB board which features most of the peripherals and connectors needed for full evaluation and utilization of the AM3352 processor.

The hardware design of AM3352-SOM development board is considered intellectual property to Olimex. The hardware layout design files are considered copyright material and would not be distributed. The original schematics, however, are distributed in a popular file format.

AM3352-SOM-EVB board is an open-source, open-hardware project and all documentation used to manufacture the board is available to the customer.

The software support for both boards is open-source and released under GPL license.

1.1 Introduction to SOM (System-On-a-Module)

OLIMEX System-on-Module (SOM) boards are powerful Linux-capable boards. They follow a low-cost modular design which allows rapid product development. Each of these boards has two parts – a main part which nests the processor, the memory and the power control unit and the peripheral part which contains the USB ports, the video output and most of the connectors. SOM designs are targeted at customers who want to apply custom modifications and own solutions based on a specific processor without having to deal with multi layer PCBs with controlled impedance and BGA assembly. This makes it possible to create simple boards (that might be manufactured by your local board manufacturer) containing only the peripherals you need with the dimensions and shape suitable for your specific solution.

Both the main part and the peripheral part of the SOM system have support in the official Android and Debian images distributed by Olimex and maintained by Olimex and the Linux community. These images are typically available at the wiki articles of the boards.

The peripheral part of the SOM design is considered Open Source HardWare (OSHW) and the customer has access to the board source files that we used to manufacture it. The part of the design that has the main microcontroller is considered proprietary design and design files would not be shared. If you are looking for open source design of the processors used please check the OLinuXino boards. OLinuXino board designs are fully open source but harder to implement in own solutions and require more of a hardware experience to do so. Nevertheless, OLinuXino boards are pretty good choice for evaluating the capabilities of the embedded processors.

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1.2 Target market of the board

Using the AM3352-SOM as a stand-alone development board would be more suitable for users with some hardware experience or people already familiar with other single-board Linux boards and designs. As mentioned in the previous chapter the board is meant to be implemented in a hardware design.

It is highly recommended to use AM3352-SOM with AM3352-SOM-EVB initially, unless you have previous experience with SOM or OLinuXino boards manufactured by OLIMEX.

Note that in the OLIMEX web-shop the product named “AM3352-SOM-EVB” includes the main board named “AM3352-SOM”.

The board's target market widens drastically when AM3352-SOM is used altogether with AM3352SOM-EVB. In that case – the combination is suitable for embedded programming enthusiasts, Linux gadget fans and also professionals (since its low cost makes it very good solution for application-orientated embedded systems). The reason for this alteration is the additional hardware that AM3352-SOM-EVB – it provides direct VGA output and easier ways to connect peripherals to the board. Generally, the processor's resources become easier to access.

In which cases a stand-alone AM3352-SOM (without AM3352-SOM-EVB) board might not be suitable for you:

1. If you are a beginner with single-board Linux computers

2. If you are an OSHW purist

3. If you are looking for more straight-forward software development and you are not going to implement the AM3352-SOM in own hardware products

In the cases above, it might be a better idea to take a look at the OLinuXino boards (like A20OLinuXino-MICRO or A20-OLiuXino-LIME2).

1.3 Features of AM3352-SOM

The AM3352-SOM board has the following set of features:

• Texas Instruments AM3352 Cortex-A8 processor running at 1GHz

• 512MB DDR3 memory

• Power supply DCDC

• MicroSD card connector

• UART console

• User LED

• Power LED

• NMI button

• Reset button

• 4 connectors × 40 pin @ 0.05" step

• Dimensions of the SOM part: (2.4×1.5)'' ~ (61×38)mm

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1.4 Board variants

At the time of writing this document, AM3352-SOM is the only Olimex-made board featuring Texas Instruments AM3352.

Other SOM boards that might be compared to functionality are: the well-supported A20-SOM, and the new powerhouse RK3188-SOM.

Another Olimex board with close characteristics is A13-SOM board. The performance of Texas Instrument’s AM3352 and Allwinner's A13 is nearly identical. The two main differences are: the A13 is cheaper; the AM3352 is documented much better. Another important point is that we consider the A13 boards mature – many of the issues had already been resolved and the performance is stable. For simpler command-line tasks A13-SOM might be the most suitable choice.

1.5 Board versions used in the manual

The documents follows the hardware layout of AM3352-SOM board revision C.

AM3352-SOM-EVB revision D peripheral board was used while writing this document.

Different board revisions might have different features or settings. It is possible that parts of this document do not apply to all board revisions.

1.6 Document organization

Each section in this document covers a separate topic, organized as follows:

– Chapter 1 is an overview of the board usage and features – Chapter 2 contains the general board diagram and layout – Chapter 3 provides a guide for quickly setting up the board and software notes – Chapter 4 describes the component that is the heart of the board: the Texas Instruments'

AM3352 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 contains the revision history, useful links and support information

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CHAPTER 2: BOARD DESCRIPTION

2. Introduction to the chapter

Here 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 AM3352-SOM board itself.

2.1 Layout (top view)

The picture below shows the top side of the board and highlights the most important parts:

The four plastic connectors (AM_CON-LCD; AM_CON-GPIO1; AM_CON-GPIO2; AM_CONGPIO3) have 0.05'' step between the pinholes. These connectors are typically used to connect to AM3352-SOM-EVB.

The pins of the UART0 header consist are suitable for powering the board (+5V and GND); and also for serial connection (TX, RX, GND).

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2.2 Layout (bottom view)

The picture below shows the bottom side of the board and highlights the most important parts:

The power LED indicates whether the board is powered properly. It is not connected to a processor pin.

The user LED is connected to processor ball B12 and can be programmed.

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CHAPTER 3: SETTING UP THE AM3352-SOM BOARD

3. Introduction to the chapter

This section helps you set up the SOM development board for the first time. Please consider the electrostatic warning to avoid damaging the board, then discover the hardware and software required to operate the board.

The procedure to power up the board is given, and a description of the default board behavior is detailed.

3.1 Electrostatic and electrical polarity warnings

AM3352-SOM boards are shipped in a protective anti-static package. The board must not be exposed to high electrostatic potentials. A grounding strap or similar protective device should be worn when handling the board. Avoid touching the component pins or any other metallic element.

Ensure that your development board gets attached to properly working hardware. If this is not possible please use isolators (like USB-ISO) to save your development board from potential over voltage.

If you connect other electrical devices to the SOM board make sure that they have equal electrical polarity. For example, when you connect a serial cable connected between a PC and the board's DEBUG port it is a good idea to have them both connected to the same electrical source (to the same utility power socket). In rare cases different polarity might cause hardware damage to the board.

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3.2 Requirements

In order to set up the AM3352-SOM board optimally one or more additional items may be needed. These might be generally placed in two categories:

Required – items that are needed in order to achieve minimum functionality; Recommended – items that is good to have in order to be able to interact with the most important

of the features of the board;

Note that if AM3352-SOM is mounted on AM3352-SOM-EVB – the requirements would be different! The requirements below are for a stand-alone use of AM3352-SOM. Refer to AM3352SOM-EVB's user's manual for adjusted requirements.

Required items:

- 5V-external power supply with proper connectors – AM3352-SOM has no power jack, neither battery connector, neither USB port; power has to be provided to the suitable pins (+5V, GND)

- Output device – USB-SERIAL-CABLE-F + personal computer with serial terminal program – AM3352-SOM lacks other options for debugging – you would need a serial cable suitable for the

3.3V UART signals

- SD card with compatible image – official images are available at the wiki article for the board.

OLIMEX AM3352-SOM User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual