ARDUINO YÚN MINI
Code: A000108
The Arduino Yún Mini is a compact version of the Arduino YUN
Arduino Yún Mini is a breadboard PCB developed with ATmega 32u4 MCU and QCA
MIPS 24K SoC CPU operating up to 400 MHz. Qualcomm Atheros CPU supports a
Linux distribution based on OpenWRT named Linino. The board has built‐ in WiFi (
IEEE 802.11b/g/n operations up to 150Mbps 1x1 2.4 GHz ) supports 20 digital
input/output pins (of which 7 can be used as PWM outputs and 12 as analog
inputs), a 16 MHz crystal oscillator, a micro USB connector, an ICSP header, two
reset buttons and one user button. The Arduino Yún Mini is similar to the Leonardo
in that the ATmega32u4 has built‐in USB communication, eliminating the need for
a secondary processor. This allows the Arduino Yún Mini to appear to a connected
computer as a mouse and keyboard, in addition to a virtual (CDC) serial / COM
port.
Arduino Microprocessor
Processor
Atheros AR9331
Architecture
MIPS 24K processor operating at up to 400 MHZ
Operating Voltage
3.3 V typ.380 mA (113~570 mA)
Flash Memory
16 MB
RAM
64 MB DDR2
Clock Speed
400 MHz
WiFi
802.11 b/g/n 2.4 GHz
Ethernet
802.3 10/100 Mbit/s
USB
2.0 Host
Arduino Microcontroller
Microcontroller
Architecture
Operating Voltage
Flash memory
SRAM
Clock Speed
Analog I/O Pins
EEPROM
DC Current per I/O Pins
General
Input Voltage
Digital I/O Pins
PWM Output
Power Consumption
PCB Size
Weight
Product Code
ATmega32u4
AVR
5V
32 KB
2.5Kb
16 MHz
12
1 KB
40 mA on I/O Pins; 50 mA on 3.3 V Pin
5 V
20
7
170 mA
23 x 71.1 mm
16g
A000108
Power
It is recommended to power the board via the micro-USB connection with 5VDC. If
you are powering the board though the Vin pin, you must supply a regulated 5VDC.
There is no on-board voltage regulator for higher voltages, which will damage the
board. The power pins are as follows:
VIN. The input voltage to the Arduino board. Unlike other Arduino boards, if you are
going to provide power to the board through this pin, you must provide a regulated 5V.
5V. The power supply used to power the microcontrollers and other components on the
board. This can come either from VIN or be supplied by USB.
3V3. A 3.3 volt supply generated by the on‐board regulator. Maximum current draw is 50
mA.
GND. Ground pins.
IOREF. The voltage at which the i/o pins of the board are operating (i.e. VCC for the
board). This is 5V on the Yún.
VCC_GT. A 2.1 volt supply generated by the on‐board regulator (designed to dogRJ45)
Memory
The ATmega32u4 has 32 KB (with 4 KB used for the boot loader). It also has 2.5
KB of SRAM and 1 KB of EEPROM (which can be read and written with the
EEPROM library). The memory on the AR9331 is not embedded inside the
processor. The RAM and the storage memory are externally connected. The Yún
Mini has 64 MB of DDR2 RAM and 16 MB of flash memory. The flash memory is
preloaded in factory with a Linux distribution based on OpenWrt called Linino OS.
You can change the content of the factory image, such as when you install a
program or when you change a configuration file. You can return to the factory
configuration by pressing the "WLAN RST" button for 30 seconds.
The Linino OS installation occupies around 6 MB of the 16 MB available of the
internal flash memory. You can use dogUSB with a micro SD card or dog eMMC a
4GB Flash if you need more disk space for installing applications.
Input and Output
Atheros AR9331 pins: Each of these pins can be used by LininoOS side as
peripherals of Linux Kernel. In addition, some pins have specialized functions:
USB: USB , USB‐ Used to connect USB MIPS with external USB devices. We suggest to use
the Add on: dogUSB or dog eMMC.
GPIO: AR_GP7, AR_GP6 These are general purpose input output commanded through the
the LininoOS distribution. They operate at 5 volts.
Ethernet port: RD , RD‐, TD , TD‐ Used to connect the MIPS Ethernet PHY with the
dogRJ45 in order to give the user an Ethernet interface.
AVR 32u4 pins: Each of the 20 digital i/o pins on the Yún Mini can be used as an
input or output, using the pinMode(), digitalWrite(), and digitalRead() functions.
They operate at 5 volts. Each pin can provide or receive a maximum of 40 mA and
has an internal pull-up resistor (disconnected by default) of 20-50 kOhms. In
addition, some pins have specialized functions:
Serial: 0‐>RX and 1Used to receive (RX) and transmit (TX) TTL serial data using the
ATmega32U4 hardware serial capability. Note that on the Yún Mini, the Serial class refers
to USB (CDC) communication; for TTL serial on pins 0 and 1, use the Serial1 class. The
hardware serials of the ATmega32U4 and the AR9331 on the Yún Mini are connected
together and are used to communicate between the two processors. As it is common in
Linux systems, the console to access the system is exposed on the serial port of the
AR9331. This means that you can access to the programs and tools offered by Linux from
your sketch.
TWI: 2 (SDA) and 3 (SCL). Support TWI communication using the Wire library. External
Interrupts: 3 (interrupt 0), 2 (interrupt 1), 0 (interrupt 2), 1 (interrupt 3) and 7 (interrupt
4). These pins can be configured to trigger an interrupt on a low value, a rising or falling
edge, or a change in value. See the attachInterrupt() function for details. It is not
recommended to use pins 0 and 1 as interrupts because they also are the hardware serial
port used to talk with the Linux processor. Pin 7 is connected to the AR9331 processor
and it may be used as handshake signal in future. Is recommended to be careful of
possible conflicts if you intend to use it as interrupt.
PWM: 3, 5, 6, 9, 10 and 11.Provide 8‐bit PWM output with the analogWrite() function.
SPI: MISO, SCK, MOSI, RXLED/SS. These pins support SPI communication using the SPI
library. Note that the SPI pins are not connected to any of the digital I/O pins as they are
on the Uno. The SPI pins are also connected to the AR9331 gpio pins, where it has been
implemented in software the SPI interface. This means that the ATMega32u4 and the
AR9331 can also communicate using the SPI protocol.
LED: L13 (pin 13). There is a built‐in LED connected to digital pin 13. When the pin is
HIGH value, the LED is on, when the pin is LOW, it's off. There are several other status
LEDs on the Yún Mini, indicating power, WLAN connection, ETH connection, and USER
functions.
Analog Inputs: A0 ‐ A5, A6 ‐ A11 (on digital pins 4, 6, 8, 9, 10, and 12). The Yún Mini has
12 analog inputs, labeled A0 through A11, all of which can also be used as digital i/o. Pins
A0‐A5 appear in the same locations as on the Uno; inputs A6‐A11 are on digital i/o pins 4,
6, 8, 9, 10, and 12 respectively. Each analog input provide 10 bits of resolution (i.e. 1024
different values). By default the analog inputs measure from ground to 5 volts, though is
it possible to change the upper end of their range using the AREF pin and the
analogReference() function.
AREF. Reference voltage for the analog inputs. Used with analogReference().
There are 3 reset buttons with different functions on the board:
Yún Mini RST. Bring this line LOW to reset the AR9331 microprocessor. Resetting the
AR9331 will cause the reboot of the linux system. All the data stored in RAM will be lost
and all the programs that are running will be terminated.
32U4 RST. Bring this line LOW to reset the ATmega32U4 microcontroller. Typically used to
add a reset button to shields which block the one on the board.
WLAN RST. This button has a double feature. Primarly serves to restore the WiFi to the
factory configuration. The factory configuration consist to put the WiFi of the Yún Mini in
access point mode (AP) and assign to it the default IP address that is 192.168.240.1, in
this condition you can connect with your computer to the a WiFi network that appear
with the SSID name "Linino‐XXXXXXXXXXXX", where the twelve 'X' are the MAC address of
your Yún Mini. Once connected you can reach the web panel of the Yún Mini with a
browser at the 192.168.240.1 or "http://linino.local" address. Note that restoring the
WiFi configuration will cause the reboot of the linux environment. To restore your WiFi
configuration you have to press and hold the WLAN RST button for 5 seconds. When you
press the button the WLAN blue LED will start to blink and will keep still blinking when
you release the button after 5 seconds indicating that the WiFi restore procedure has
been recorded. The second function of the WLAN RST button is to restore the linux image
to the default factory image. To restore the linux environment you must press the button
for 30 seconds. Note that restoring the factory image make you lose all the files saved
and softwares installed on the on‐board flash memory connected to the AR9331.
Communication
The Yún Mini has a number of facilities for communicating with a computer,
another Arduino, or other microcontrollers. The ATmega32U4 provides a dedicated
UART TTL (5V) serial communication. The 32U4 also allows for serial (CDC)
communication over USB and appears as a virtual com port to software on the
computer. The chip also acts as a full speed USB 2.0 device, using standard USB
COM drivers. The Arduino software includes a serial monitor which allows simple
textual data to be sent to and from the Arduino board. The RX and TX LEDs on the
board will flash when data is being transmitted via the USB connection to the
computer. Digital pins 0 and 1 are used for serial communication between the 32U4
and the AR9331. You can use Ciao library to communication between the
processors.
Arduino Ciao is an easy-to-use and powerful technology that enables Arduino
sketches to communicate intuitively with the "outside World". It aims to simplify
interaction between microcontroller and Linino OS, allowing a variety of
connections with most common protocols, third-party services and social networks.
Ciao has been designed and developed to be modular and easily configurable. Its
goal is to support several connectors capable of interacting with the system
resources (filesystem, console, memory) and to communicate with the most common
and useful protocols (XMPP, HTTP, WebSocket, COAP, etc..) and applications
(Jabber, WeChat, Twitter, Facebook, etc.).
Ciao Library is a lightweight library that can be used inside sketches for MCU to
send and receive data, via serial communication, in a simple and intuitive way. A
SoftwareSerial library allows for serial communication on any of the Yún mini's
digital pins. Pins 0 and 1 should be avoided as they are used by the Bridge library.
The ATmega32U4 also supports I2C (TWI) and SPI communication. The Arduino
software includes a Wire library to simplify use of the I2C bus;. For SPI
communication, use the SPI library. The Yún Mini appears as a generic keyboard
and mouse, and can be programmed to control these input devices using the
Keyboard and Mouse classes. The onboard Ethernet and WiFi interfaces are exposed
directly to the AR9331 processor. To send and receive data through them, use the
Bridge library. The Yún Mini also has USB host capabilities through Linino OS.
You can connect peripherals like USB flash devices for additional storage,
keyboards, or webcams. You may need to download and install additional software
for these devices to work.
Programming
The Arduino Yún Mini can be programmed with the Arduino software (download)
or the Linino IO (www.linino.org). Using Arduino IDE Select "Arduino Yún mini
from the Tools > Board menu (according to the microcontroller on your board). The
ATmega32U4 on the Arduino Yún Mini comes preburned with a bootloader that
allows you to upload new code to it without the use of an external hardware
programmer. It communicates using the STK500 protocol. You can also bypass the
bootloader and program the microcontroller through the SPI signals that are
available on the pin headers.
Automatic (Software) Reset
Rather than requiring a physical press of the reset button before an upload, the Yún
Mini is designed in a way that allows it to be reset by software running on a
connected computer. The reset is triggered when the Yún Mini's virtual (CDC)
serial / COM port is opened at 1200 baud and then closed. When this happens, the
processor will reset, breaking the USB connection to the computer (meaning that
the virtual serial / COM port will disappear). After the processor resets, the
bootloader starts, remaining active for about 8 seconds. The bootloader can also be
initiated by pressing the reset button on the Yún Mini. Note that when the board
first powers up, it will jump straight to the user sketch, if present, rather than
initiating the bootloader. Because of the way the Yún Mini handles reset it's best to
let the Arduino software try to initiate the reset before uploading, especially if you
are in the habit of pressing the reset button before uploading on other boards. If the
software can't reset the board you can always start the bootloader by pressing the
reset button on the board.
Physical Characteristics
The maximum length and width of the Yún Mini PCB are 71.12 mm and 22.86 mm
respectively. Weight of the board is 16 g.
Add on
The Arduino Yun Mini can be complemented by three accessories: the dogRJ45, the
dogUSB and the dog eMMC. The first is an Ethernet port that can be added to the
Arduino YUN Mini if one needs this type of port for their specific project. The
second one, dogUSB, is a USB port featuring also a slot for a mini SD to extend the
memory of the board. The last one, which is dogUSB eMMC, is really the latest
novelty in terms of accessories: it’s a USB port with an integrated 4 Giga of Flash.
The user can add either a single accessory or two, according to their needs.
dogRJ45
IEEE 802.3 fast ethernet switch
10/100 Mbps fast ethernet port
dogUSB
USB A type connector with USB 2.0 hub
Micro SD connector with card reader
dog eMMC
4 GB Flash
USB port type A
https://store.arduino.cc/usa/arduino-yun 12-4-17