
Atmel AVR 8-bit Microcontrollers
ATtiny104 Xplained Nano
USER GUIDE
Preface
The Atmel® ATtiny104 Xplained Nano evaluation kit is a hardware platform to
evaluate the ATtiny104 microcontroller.
Supported by the Atmel Studio integrated development platform, the kit
provides easy access to the features of the Atmel ATtiny104 and explains
how to integrate the device in a custom design.
The Xplained Nano MCU series evaluation kits include an on-board mini
embedded programmer, and no external tools are necessary to program the
ATtiny104.
Atmel-42671A-ATtiny104-Xplained-Nano_User Guide-02/2016

Table of Contents
Preface............................................................................................................................ 1
1. Introduction................................................................................................................3
1.1. Features....................................................................................................................................... 3
1.2. Kit Overview................................................................................................................................. 3
2. Getting Started...........................................................................................................4
2.1. Xplained Nano Quick Start........................................................................................................... 4
2.2. Design Documentation and Relevant Links................................................................................. 4
3. Xplained Nano........................................................................................................... 5
3.1. Mini Embedded Debugger............................................................................................................5
3.1.1. Xplained Nano Clock Output......................................................................................... 5
3.2. Power Sources............................................................................................................................. 5
3.3. Xplained Nano Standard Pin-Out................................................................................................. 6
3.3.1. Standard Pin-Out for TPI............................................................................................... 6
3.4. Disconnecting mEDBG.................................................................................................................7
4. Hardware User Guide................................................................................................9
4.1. Connectors................................................................................................................................... 9
4.1.1. ATtiny104 Xplained Nano Pin-Out................................................................................. 9
4.2. Current Measurement...................................................................................................................9
4.3. Peripherals................................................................................................................................. 10
4.3.1. LED..............................................................................................................................10
4.3.2. Mechanical Buttons..................................................................................................... 10
5. Embedded Debugger Implementation..................................................................... 11
5.1. Tiny Program Interface............................................................................................................... 11
5.2. Virtual COM Port.........................................................................................................................11
6. Hardware Revision History and Known Issues........................................................12
6.1. Identifying Product ID and Revision........................................................................................... 12
6.2. Revision 2...................................................................................................................................12
7. Document Revision History..................................................................................... 13
8. Evaluation Board/Kit Important Notice.....................................................................14
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1. Introduction
RESET
TPI DATA
TPI CLK
NC
VREG
VUSB
GND
CLK OUT
CDC TX
CDC RX
VCC
PA0
PA1
PA2
PA3
PA4
PA5
GND
PB3
PB2
PB1
PB0
PA7
PA6
Micro USB Connector
User LED User button
mEDBG
ATtiny104
Power disconnect mEDBG disconnectStatus LED
TPI CLK
TPI DATA
RESET
USER LED
USER BTN
CDC TX
CDC RX
Power
Ground
Clock
Serial
Target I/O
Shared I/Os
Program/Debug
1.1. Features
• ATtiny104 microcontroller
• One yellow user LED
• One mechanical button
• mEDBG
– Auto-ID for board identification in Atmel Studio
– One green board status LED
– Programming
– Virtual COM port (CDC)
• USB powered
1.2. Kit Overview
The Atmel ATtiny104 Xplained Nano evaluation kit is a hardware platform to evaluate the Atmel
ATtiny104.
Figure 1-1. ATtiny104 Xplained Nano Evaluation Kit Overview
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2. Getting Started
2.1. Xplained Nano Quick Start
Steps to start exploring the Atmel Xplained Nano platform:
1. Download Atmel Studio
2. Launch Atmel Studio
3. Connect a USB cable (Standard-A to Micro-B or Micro-AB) between the PC and the USB port on
the kit
When the Xplained Nano kit is connected to your computer for the first time, the operating system will
perform a driver software installation. The driver file supports both 32- and 64-bit versions of Microsoft
Windows® XP, Windows Vista®, Windows 7, Windows 8, and Windows 10. The drivers for the kit are
included with Atmel Studio.
Once the Xplained Nano board is powered the green status LED will blink and Atmel Studio will auto
detect which Xplained Nano board is connected. Atmel Studio will present relevant information like
datasheets and kit documentation. The ATtiny104 device is programmed by the on-board Mini Embedded
Debugger and therefore no external programmer tool is required.
2.2. Design Documentation and Relevant Links
The following list contains links to the most relevant documents and software for the ATtiny104 Xplained
Nano.
• Xplained products - Atmel Xplained evaluation kits are a series of easy-to-use evaluation kits for
Atmel microcontrollers and other Atmel products. For low pin-count devices the Xplained Nano
series provides a minimalistic solution with access to all I/O pins of the target microcontroller.
Xplained Mini kits are for medium pin-count devices and adds Arduino Uno compatible header
footprint and a prototyping area. Xplained Pro kits are for medium to high pin-count devices, they
features advanced debugging and standardized extensions for peripheral functions. All these kits
have on board programmers/debuggers which creates a set of low-cost boards for evaluation and
demonstration of features and capabilities of different Atmel products.
• Atmel Studio - Free Atmel IDE for development of C/C++ and assembler code for Atmel
microcontrollers.
• Atmel sample store - Atmel sample store where you can order samples of devices.
• Atmel Data Visualizer - Atmel Data Visualizer is a program used for processing and visualizing
data. Data Visualizer can receive data from various sources such as the Embedded Debugger Data
Gateway Interface found on Xplained Pro boards and COM ports.
• Design Documentation - Package containing CAD source, schematics, BOM, assembly drawings,
3D plots, layer plots etc.
• Hardware Users Guide in PDF format - PDF version of this User Guide.
®
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3. Xplained Nano
Xplained Nano is an evaluation platform that provides a set of small boards with access to all
microcontoller I/O's. The platform consists of a series of low pin-count Microcontroller (MCU) boards,
which are integrated with Atmel Studio to present relevant user guides, application notes, datasheets, and
example code through Atmel Studio. The platform also features a Virtual COM port for serial
communication to a host PC.
3.1. Mini Embedded Debugger
The ATtiny104 Xplained Nano contains the Atmel Mini Embedded Debugger (mEDBG) for on-board
programming. The mEDBG is a composite USB device of two interfaces; a debugger and a Virtual COM
Port.
Together with Atmel Studio, the mEDBG debugger interface can program the ATtiny104. On ATtiny104
Xplained Nano, the TPI interface is connected between the mEDBG and the ATtiny104.
The Virtual COM Port is connected to a UART on the ATtiny104 and provides an easy way to
communicate with the target application through terminal software. It offers variable baud rate, parity, and
stop bit settings.
Note: The settings on the ATtiny104 must match the settings given in the terminal software.
Info: The virtual COM port in the mEDBG requires the terminal software to set the data
terminal ready (DTR) signal to enable the UART pins connected to the ATtiny104. If the DTR
signal is not enabled the UART pins on the mEDBG is kept in high-z (tristate) rendering the
COM port unusable. The DTR signal is set automatically by some terminal software, but it may
have to be manually enabled in your terminal.
The mEDBG controls one status LED on ATtiny104 Xplained Nano. The table below shows how the LED
is controlled in different operation modes.
Table 3-1. mEDBG LED Control
Operation mode Status LED
Power up LED is lit briefly
Normal operation LED is not lit
Programming Activity indicator; LED flashes when programming/
3.1.1. Xplained Nano Clock Output
The mEDBG output its CPU clock to the CLK pin 8 as shown in Xplained Nano Standard Pin-Out on page
6. The clock output can be used to feed the target device with a more accurate clock if this is needed
for the application.
3.2. Power Sources
The ATtiny104 Xplained Nano kit can be powered by different sources. By default the kit will have a 5V
supply and the voltage is taken directly from the USB port through a 500mA PTC fuse. The voltage from
the USB connector can vary between 4.4V to 5.25V (according to USB spec).
debugging with the mEDBG
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