OLIMEX OLIMEXINO-32U4 User manual

OLIMEXINO-32U4 development board
USER’S MANUAL
Revision H, April 2017
Designed by OLIMEX Ltd, 2013
All boards produced by Olimex LTD are ROHS compliant

OLIMEX© 017 OLIMEXINO-3 U4 user's manual
© 017 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.
he 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.
HERE IS NO WARRAN Y FOR HE DESIGN MA ERIALS AND HE COMPONEN S
USED O CREA E OLIMEXINO-32U4. HEY ARE CONSIDERED SUI ABLE ONLY
FOR OLIMEXINO-32U4.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
Table of Contents
CHA TER 1 OVERVIEW ......................................................................................... 5
1. Introduction to the chapter ....................................................................................................... 5
1.1 Features ..................................................................................................................................... 5
1.2 Similar boards .......................................................................................................................... 6
1.3 Organization ............................................................................................................................. 6
CHA TER 2 INTRODUCTION TO ARDUINO ..................................................... 7
2. What is Arduino? ....................................................................................................................... 7
2.1 First steps with Arduino IDE .................................................................................................. 8
CHA TER 3 SETTING U THE OLIMEXINO-32U4 BOARD ......................... 10
3. Introduction to the chapter ..................................................................................................... 10
3.1 Electrostatic warning ............................................................................................................. 10
3.2 Requirements ......................................................................................................................... 10
3.3 Powering the board ................................................................................................................ 10
3.4 Prebuilt software .................................................................................................................... 10
CHA TER 4 OLIMEXINO-32U4 BOARD DESCRI TION ............................... 11
4. Introduction to the chapter ..................................................................................................... 11
4.1 Layout (top view) ................................................................................................................... 11
CHA TER 5 THE ATMEGA32U4 MICROCONTROLLER .............................. 12
5. Introduction to the chapter ..................................................................................................... 12
5.1 he microcontroller's features .............................................................................................. 12
CHA TER 6 CONTROL CIRCUITY .................................................................... 14
6. Introduction to the chapter ..................................................................................................... 14
6.1 Reset ........................................................................................................................................ 14
6.2 Clock ....................................................................................................................................... 14
CHA TER 7 HARDWARE ...................................................................................... 15
7. Introduction to the chapter ..................................................................................................... 15
7.1 Battery connector ................................................................................................................... 15
7.2 ICSP pin holes ........................................................................................................................ 15
7.3 UEX ...................................................................................................................................... 16
7.4 Arduino shield pin holes ........................................................................................................ 17
7.5 USB mini connector ............................................................................................................... 18
7.6 Jumper description ................................................................................................................ 18
7.7 Additional hardware components ........................................................................................ 19
CHA TER 8 MEMORY AND BLOCK DIAGRAM ............................................. 20
8. Introduction to the chapter ..................................................................................................... 20
8.1 Memory organization ............................................................................................................ 21
CHA TER 9 SCHEMATICS ................................................................................... 22
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9. Introduction to the chapter ..................................................................................................... 22
9.1 Eagle schematic ...................................................................................................................... 22
9.2 Physical dimensions ............................................................................................................... 24
CHA TER 10 REVISION HISTORY ..................................................................... 25
10. Introduction to the chapter ................................................................................................... 25
10.1 Document revision ............................................................................................................... 25
10.2 Board revision ...................................................................................................................... 26
10.3 Web page of your device ...................................................................................................... 27
10.4 Warranty and returns .......................................................................................................... 28
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHA TER 1 OVERVIEW
1. Introduction to the chapter
Thank you for choosing the OLIMEXINO-3 U4 development board from Olimex! This document
provides a User’s Guide for the Olimex OLIMEXINO-3 U4 development 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 OLIMEXINO-3 U4 development board enables code development of applications running on
the ATmega3 U4 microcontroller, manufactured by Atmel Corporation.
1.1 Features
•Leonardo design – no FTDI chip, the MCU directly handles the virtual COM
•ATMEGA3 U4 microcontroller, all in one USB communication no need for external FTDI
chip.
•Input power supply 7-1 VDC
•ULTRA LOW POWER voltage regulators and the consumption is only few microamps,
which enables hand-held and battery powered applications.
•Li-Ion rechargeable battery power supply option with BUILD-IN on board charger, so when
you attach battery it is automatically charged and kept in this state until the other power
source (USB or external adapter) is removed and it AUTOMATICALLY will power the
board – no jumpers, no switches!
•Works both on 3.3V and on 5V which is selectable with jumper, so 3.3V and 5V shields can
be used
•UEXT connector which allow many existing modules like RF, ZIGBEE, GSM, GPS to be
connected
•Allows RTC – Real Time Clock (Q1 can be replaced by RTC).
•NOISE IMMUNE design
•the LEDs and the button BUT are on the edge of the board so there is easy access even if the
boards have shields on them
•all components are LOWER than the connectors, so the shields do not interference with
them
•mini USB connector is used -it is common and used in most cell phones, so you don't have
to buy other cables
•Original design had a flaw – the connectors were not spaced at 0.1" which made bread board
use impossible, to keep the compatibility we have the original spacing but we also added a
0.1'' connector which customer can use with bread boards (and jumper wires) saving the
hustle of soldering
•All signals on the connectors are printed on top of the board, so when you check with probe
you know exactly which port you are measuring
•4 mount holes make board attachment easier
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
1.2 Similar boards
OLIMEXINO-3 U4 is an ARDUINO-LEONARDO-like board with ATmega3 U4.
It is a powerful board considering its low price but yet a starter board for the Arduino family.
The more powerful Arduino board we have in the range is OLIMEXINO-3 8 – based on Arduino
Duemilanove. It has a more sophisticated supply circuit, USB OTG connector and there are more
Arduino projects available.
1.3 Organization
Each section in this document covers a separate topic, organized as follow:
–Chapter 1 is an overview of the board usage and features
–Chapter has a short introduction to Arduino platform and its derivatives Pinguino and
Maple
–Chapter 3 provides a guide for quickly setting up the board
–Chapter 4 contains the general board diagram and layout
–Chapter 5 describes the component that is the heart of the board: the ATmega3 U4
microcontroller
–Chapter 6 is an explanation of the control circuitry associated with the microcontroller to
reset. Also shows the clocks on the board
–Chapter 7 covers the connector pinout, peripherals and jumper description
–Chapter 8 shows the processor diagram and memory map
–Chapter 9 provides the schematics
–Chapter 10 contains the revision history
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHA TER 2 INTRODUCTION TO ARDUINO
2. What is Arduino?
Arduino is an open-source electronics prototyping platform, designed to make the process of using
electronics in multidisciplinary projects easily accessible. The hardware consists of a simple open
hardware design for the Arduino board with an Atmel AVR processor and on-board I/O support. The
software consists of a standard programming language and the boot loader that runs on the board.
Arduino hardware is programmed using a Wiring-based language (syntax + libraries), similar to C+
+ with some simplifications and modifications, and a Processing-based Integrated Development
Environment (IDE).
The project began in Ivrea, Italy in 005 aiming to make a device for controlling student-built
interaction design projects less expensively than other prototyping systems available at the time. As
of February 010 more than 1 0,000 Arduino boards had been shipped. Founders Massimo Banzi
and David Cuartielles named the project after a local bar named Arduino. The name is an Italian
masculine first name, meaning "strong friend". The English pronunciation is "Hardwin", a
namesake of Arduino of Ivrea.
More information could be found at the creators web page http://arduino.cc/ and in the Arduino
Wiki http://en.wikipedia.org/wiki/Arduino
To make the story short – Arduino is easy for beginners who lack Electronics knowledge, but also
does not restrict professionals as they can program it in C++ or mix of Arduino/C++ language.
There are thousands of projects which makes it easy to startup as there is barely no field where
Arduino enthusiasts to have not been already.
Arduino has inspired two other major derivatives – MAPLE and PINGUINO. Based on 8-bit AVR
technology the computational power of Arduino boards is modest, this is why a team from MIT
developed the MAPLE project which is based on ARM7 STM3 F103RBT6 microcontroller. The
board has same friendly IDE as Arduino and offers the same capabilities as hardware and software
but runs the Arduino code much faster. The Maple project can be found at http://leaflabs.com
In parallel with Arduino another project was started called PINGUINO. This project chose its first
implementation to be with PIC microcontrollers, as AVRs were hard to find in some parts of the
world like South America so it is likely to see lot of PINGUINO developers are from that part of the
world. PINGUINO project founders decided to go with Python instead Java for processing
language. For the moment PINGUINO is much more flexible than Arduino as it is not limited to
8bit microcontrollers. Currently the IDE, which has GCC in background, can support 8-bit PIC
microcontrollers, 3 bit PIC3 (MIPS) microcontrollers and ARM7/CORTEXM3 microcontrollers
which makes PINGUINO very flexible because once you make your project you can migrate easily
through different hardware platforms and not being bound to a single microcontroller manufacturer.
The PINGUINO project can be found at: http://www.pinguino.cc.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
2.1 First steps with Arduino IDE
Depending when you purchased the board there are two scenarios since the PID (product ID) which
is stored in the firmware and expected by the IDE is different between versions 1.0.0 and 1.0.1
(1.0.1 is the first release of the Arduino IDE with official support for Leonardo).
2.1.1 For purchases after the official release of Leonardo
Boards produced after the official release of Arduino Leonardo have the latest bootloader available
with the adjusted bootloader PID. Download the latest Arduino IDE and extract the package. You
can find the needed driver for the bootloader located in folder /drivers. You click update on the
device in device manager and point the installer to the /drivers folder.
Then launch Arduino IDE and set the correct board and COM port in TOOLS menu.
From File->Open navigate to the examples folder which is found in the Arduino IDE installation
folder. Choose a simple example to begin with like BlinkWithoutDelay.ino and open it. Click verify
and after it compiles click “Upload”. Voila, you have uploaded code to your Arduino device.
Now start exploring the world of Arduino! More info and help on the software can be found and the
official Arduino web site: http://www.arduino.cc/.
2.1.2 For purchases before the official release of Leonardo
If you have purchased the OLIMEXINO-3 U4 before the official release of the Arduino Leonardo
board there are two scenarios for using Arduino IDE:
1) Download Arduino IDE 1.0 RC or Arduino IDE 1.0.0. When you extract the package check if
the Arduino Leonardo section is the \hardware\arduino\boards is uncommented. If the section has
number signs (#) infront remove the number signs (#).
) If you want to use the latest version (which by the time of writing is 1.0.1) you would need to
change to bootloader firmware. This will require an AVR programmer tool.
You can get the bootloader in .elf format from our web site. You can also use the original bootloader
hex if you set the fuses and lock bits for the processor as follows:
low_fuses=0xff
high_fuses=0xd8
extended_fuses=0xcb
lock_bits (choose “SPM Prohibited in Boot Section”) from the drop down menu which will set the
bits either to EF or F)
After you have downloaded and extracted the desired IDE you need to install the driver for your
operating system. You can find the needed driver for the bootloader located in folder /drivers. You
click update on the device in device manager and point the installer to the /drivers folder.
Then launch Arduino IDE and set the correct board and COM port in TOOLS menu.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
From File->Open navigate to the examples folder which is found in the Arduino IDE installation
folder. Choose a simple example to begin with like BlinkWithoutDelay.ino and open it. Click verify
and after it compiles click “Upload”. Voila, you have uploaded code to your Arduino device.
Now start exploring the world of Arduino! More info and help on the software can be found and the
official Arduino web site: http://www.arduino.cc/.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHA TER 3 SETTING U THE OLIMEXINO-32U4 BOARD
3. Introduction to the chapter
This section helps you set up the OLIMEXINO-3 U4 development board for the first time.
Please consider first 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 warning
OLIMEXINO-3 U4 is 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.
3.2 Requirements
In order to set up the OLIMEXINO-3 U4, the following items are required:
If using the free ARDUINO IDE the ONLY requirement is a miniUSB to USB-A cable to connect
to a computer.
If you want to upgrade the bootloader, or program the board without the ARDUINO-IDE there are
pinouts for ICSP programmer (note that there isn't a connector mounted). You can use our AVR-
ISP-MK , or AVR-ISP500 programmer for custom programming without ARDUINO IDE.
Having an AVR programmer is highly advisable since the bootloader software is still not perfect
and it is possible to destroy it only by software means (remap pins used for programming) which
would require reinstalling the bootloader.
3.3 owering the board
The OLIMEXINO-3 U4 board is self-powered by the miniUSB if it is connected to a USB hub of a
computer. Alternatively, it can be powered via the POWER JACK by 7Vdc to 1 Vdc or via the
3.7V-LI_BAT connector by 3.7V battery.
The bootloader starts automatically.
On powering the board PWR_LED should turn on. RXLED and TXLED should turn on and
monitor the send receive on the virtual COM port. LED1 and LED should start blinking.
3.4 rebuilt software
The board comes with prebuilt ARDUINO bootloader. The different part between the other
Arduinos and Leonardo is that Leonardo doesn't use FTDI chip nor external chip for the virtual
COM port but it is handled by the ATmega3 U4.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHA TER 4 OLIMEXINO-32U4 BOARD DESCRI TION
4. Introduction to the chapter
Here you get acquainted with the main parts of the board. Note the names used on the board differ
from the names used to describe them. For the actual names check the OLIMEXINO-3 U4 board
itself.
4.1 Layout (top view)
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CHA TER 5 THE ATMEGA32U4 MICROCONTROLLER
5. Introduction to the chapter
In this chapter is located the information about the heart of OLIMEXINO-3 U4 – its
microcontroller. The information is a modified version of the datasheet provided by its
manufacturers.
5.1 The microcontroller's features
• High Performance, Low Power AVR® 8-Bit Microcontroller
• Advanced RISC Architecture
– 135 Powerful Instructions – Most Single Clock Cycle Execution
– 3 ×8 General Purpose Working Registers
– Fully Static Operation
– Up to 16 MIPS Throughput at 16 MHz
– On-Chip -cycle Multiplier
• Non-volatile Program and Data Memories
– 3 K Bytes of In-System Self-Programmable Flash
– .5K Bytes Internal SRAM
– 1K Bytes Internal EEPROM
– Write/Erase Cycles: 10,000 Flash/100,000 EEPROM
– Data retention: 0 years at 85°C/ 100 years at 5°C(1)
– Optional Boot Code Section with Independent Lock Bits
In-System Programming by On-chip Boot Program
True Read-While-Write Operation
All supplied parts are preprogramed with a default USB bootloader
– Programming Lock for Software Security
• JTAG (IEEE std. 1149.1 compliant) Interface
– Boundary-scan Capabilities According to the JTAG Standard
– Extensive On-chip Debug Support
– Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG
Interface
• USB .0 Full-speed/Low Speed Device Module with Interrupt on Transfer Completion
– Complies fully with Universal Serial Bus Specification Rev .0
– Supports data transfer rates up to 1 Mbit/s and 1.5 Mbit/s
– Endpoint 0 for Control Transfers: up to 64-bytes
– 6 Programmable Endpoints with IN or Out Directions and with Bulk, Interrupt or
Isochronous Transfers
– Configurable Endpoints size up to 56 bytes in double bank mode
– Fully independent 83 bytes USB DPRAM for endpoint memory allocation
– Suspend/Resume Interrupts
– CPU Reset possible on USB Bus Reset detection
– 48 MHz from PLL for Full-speed Bus Operation
– USB Bus Connection/Disconnection on Microcontroller Request
– Crystal-less operation for Low Speed mode
• Peripheral Features
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– On-chip PLL for USB and High Speed Timer: 3 up to 96 MHz operation
– One 8-bit Timer/Counter with Separate Prescaler and Compare Mode
– Two 16-bit Timer/Counter with Separate Prescaler, Compare- and Capture Mode
– One 10-bit High-Speed Timer/Counter with PLL (64 MHz) and Compare Mode
– Four 8-bit PWM Channels
– Four PWM Channels with Programmable Resolution from to 16 Bits
– Six PWM Channels for High Speed Operation, with Programmable Resolution from
to 11 Bits
– Output Compare Modulator
– 1 -channels, 10-bit ADC (features Differential Channels with Programmable Gain)
–Programmable Serial USART with Hardware Flow Control
–Master/Slave SPI Serial Interface
– Byte Oriented -wire Serial Interface
– Programmable Watchdog Timer with Separate On-chip Oscillator
– On-chip Analog Comparator
– Interrupt and Wake-up on Pin Change
– On-chip Temperature Sensor
• Special Microcontroller Features
– Power-on Reset and Programmable Brown-out Detection
– Internal 8 MHz Calibrated Oscillator
– Internal clock prescaler & On-the-fly Clock Switching (Int RC / Ext Osc)
– External and Internal Interrupt Sources
– Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby, and
Extended Standby
• I/O and Package
– All I/O combine CMOS outputs and LVTTL inputs
– 6 Programmable I/O Lines
– 44-lead QFN Package, 7×7mm
• Operating Voltages
– .7 – 5.5V
• Operating temperature
– Industrial (-40°C to +85°C)
• Maximum Frequency
– 8 MHz at .7V – Industrial range
– 16 MHz at 4.5V – Industrial range
For comprehensive information on the microcontroller visit the Atmel web page for a datasheet.
At the moment of writing the microcontroller datasheet can be found at the following link:
http://www.atmel.com/Images/doc7766.pdf
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHA TER 6 CONTROL CIRCUITY
6. Introduction to the chapter
Here you can find information about reset circuit, power circuit and quartz crystal locations.
6.1 Reset
OLIMEXINO-3 U4 reset circuit includes R7 (4.7kΩ), R8 (330Ω), D1 (Shottky diode),
ATmega3 U4 pin 13 (#RESET) and a RESET button. Note that it also can be found at the ICSP
header pin 5 and power connector pin 1.
6.2 Clock
16MHz quartz crystal Q1 is found at pins 16 and 17 of the processor.
By default OLIMEXINO-3 U4 operates at 5V, which allows the main microcontroller
(ATmega3 u4) to operate properly at the maximum clock speed (16 MHz). The ATmega3 u4
would work properly at 16MHz only if powered by at least 4.5V.
If you decide to change the position of the jumper 3.3V/5V jumper to 3.3V position, please note
that, at 3.3V, the maximum frequency that can be achieved with ATmega3 u4 is around 10MHz,
thus the 16MHz operation is a significant overclock. Yet, our tests proved that the board works
reliably with a 16MHz quartz even at 3.3V.
IMPORTANT: If the board has a quartz crystal rotated at 45 degrees relative to the pads provided
do not panic. This is normal. We have two types of such crystals – one of them requires 4 pads, the
other only pads. That is why we have provided 4 pads to be able to fit both crystals. All boards
Olimex manufactures pass automatized optical inspection after assembly and obvious misplacement
like this is impossible to occur.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHA TER 7 HARDWARE
7. Introduction to the chapter
In this chapter are presented the connectors that can be found on the board all together with their
pinout. Jumpers functions are described. Notes and info on specific peripherals are presented. Notes
regarding the interfaces are given.
7.1 Battery connector
The battery connector is suitable for 3.7V LiPo batteries. The board has a built-in charger circuit, so
when the main power supply is restored the battery would get recharged automatically.
Pin # Signal Name
1VBAT
2GND
7.2 ICS pin holes
The 6 pin ICSP header provides interface for custom programming/debugging outside of the
Arduino IDE. Note the pin holes doesn't have a connector mounted over – you have to mount
it/solder it yourself. The pinout can be found in the table below. It is important to check the jumper
configuration for proper use of the ICSP pin hole.
ICSP pin holes
Pin # Signal name Pin # Signal name
1D14(MISO) 4D16(MOSI)
2Vcc 5RESET
3D15(SCK) 6GND
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7.3 UEXT
OLIMEXINO-3 U4 board has UEXT connector and can interface Olimex's UEXT modules.
For more information on our UEXT modules please visit:
https://www.olimex.com/Products/Modules/UEX /
Pin # Signal name
1VDD out (3.3V or 5V)
2GND
3D1(TXD)
4D0(RXD)
5D3(SC )
6D2(SDA)
7D14(MISO)
8D16(MOSI)
9D15(SCK)
10 D13(UEXT_#CS)
IMPORTANT: Be careful with the voltage output available at pin #1. The on-board 3.3V/5V switch
also controls the voltage output available at pin #1 of the UEXT. Do not connect Olimex modules
when the switch is set to 5V position, unless you are 100% sure that these UEXT modules work fine
at 5V (most Olimex modules can not work properly at 5V, only at 3.3V)
It is important to note that there are 4.7k pull-up resistors on the I C lines – SCL/SDA (D3 and D
respectively). You can disconnect/disable the resistors by cutting between the pads of the small
SMT jumpers R11_E and R1 _E.
The chip select pin – CS (D13) also has a 4.7k pull-up resistor which might be disabled by cutting
R13_E.
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7.4 Arduino shield pin holes
For your convenience the pads are named individually near each of them. Please take extra care
about the numbering but consider that there might be offset.
Pad Name Signal Pad Name Signal
POWER CON1 DIGITA CON2
RST RESET 0 PF7/ADC7/TDI
3V3 +3.3 V 1 PF6/ADC6/TDO
5V +5 V 2 PF5/ADC5/TMS
GND GROUND 3 PF4/ADC4/TCK
GND GROUND 4 PF1/ADC1
VIN V in 5 PF0/ADC0
DIGITA CON3 DIGITA CON4
D0(RXD) PD2/RXD1/INT2 D8(UEXT_PWR_E) RB4/PCINT4/ADC11
D1(TXD) PD3/TXD1/INT3 D9(LED2) PB5/PCIN5/OC1A/#OC4B/
ADC12
D2(SD ) PD1/SDA/INT1 D10 PB6/PCINT6/OC1B/OC4B/ADC1
3
D3(SCL) PD0/OC0B/SC /I
NT0 D11 PB7/PCINT7/OC0A/OC1C/ #RTS
D4 PD4/ICP1/ADC8 D12 PD6/T1/#OC4D/ADC9
D5 PC6/OC3A/
#OC4A D13(UEXT_#CS) PC7/ICP3/C K0/OC4A
D6 PD7/T0/OC4D/AD
C10 GND GND
D7(LED1) INT6/AIN0/PE6 REF AREF
SD D2(SDA)
SCL D3(SC )
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
7.5 USB mini connector
Note that the USB is configured only as device.
Pin # Signal Name
1+5V
2D-
3D+
4Not connected
5GND
7.6 Jumper description
3.3V/5V
This jumper controls whether the board is powered by 3.3Vdc source or 5Vdc. It is provided to
ensure compatibility with both original 5V shields and 3.3V modules.
Important! Changing this jumper also changes the voltage available at pin #1 of UEXT and also the
voltage levels of all data signals available there (UART, SPI, I C). Most Olimex-manufactured
UEXT modules work at 3.3V – they would get damaged if the jumper is set 3.3V. When using
Olimex MOD- board on this UEXT ensure the jumper is set to 3.3V, else you might damage the
module.
Default position is 2-3 – 5Vdc.
AGND_E
When closed enables analog GND. SMD jumper.
Default state is closed.
FE 3_E
When closed connects D8 from Arduino shield connector to FET3 so you can control the power on
the UEXT by software means.
When open D8 becomes GPIO. This is a SMD type of jumper.
Default state is closed.
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LED1_E
When closed enables LED1. SMD jumper.
Default state is closed.
LED2_E
When closed enables LED . SMD jumper.
Default state is closed.
RXLED_E
When closed enables RXLED. SMD jumper.
Default state is closed.
XLED_E
When closed enables TXLED. SMD jumper.
Default state is closed.
R11_E, R12_E, R13_E
When these jumpers are closed they enable 4.7k Ohm pull-up resistors on each of the I C lines
(R11_E is responsible for the resistor of SCL line, R1 _E – for the SDA line, R13_E – for the
UEXT_CS). SMD jumpers.
Default state for all three is closed.
7.7 Additional hardware components
The components below are mounted on the OLIMEXINO-3 U4 board but are not discussed above.
They are listed here for completeness:
General-purpose button
general purpose LEDs
LEDs showing virtual port activity
Note that connectors on the CON1, CON , CON3, CON4 are soldered/mounted.
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OLIMEX© 017 OLIMEXINO-3 U4 user's manual
CHAP ER 8 MEMORY AND BLOCK DIAGRAM
8. Introduction to the chapter
Below is located the block diagram of the processor and on the next page you can find a memory
map for this family of processors. It is strongly recommended to refer to the original datasheet
released by Atmel for ones of higher quality.
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