Arduino Pro Mini 5V
The Arduino Pro Mini is a micro-controller board base on the ATmega328 (datasheet). It has 14 digital input/output pins (of which 6 can be use as PWM outputs), 6 analog inputs, an on-board resonator, a reset button, and holes for mounting pin headers. A six pin header can be connect to an FTDI cable to provide USB power and communication to the board.
The Arduino Pro Mini 5V is intend for semi-permanent installation in objects or exhibitions. The board comes without pre-mount headers, allowing the use of various types of connectors or direct soldering of wires. The pin layout is compatible with the Arduino Mini.
There are two version of the Pro Mini. One runs at 3.3V and 8 MHz, the other at 5V and 16 MHz. This is 5V version.
The Arduino Pro Mini can be powered with an FTDI cable or breakout board connected to its six pin header, or with a regulated 3.3V or 5V supply (depending on the model) on the Vcc pin. There is a voltage regulator on board so it can accept voltage up to 12VDC. If you’re supplying unregulated power to the board, be sure to connect to the “RAW” pin on not VCC.
The power pins are as follows:
- RAW. For supplying a raw voltage to the board.
- VCC. The regulated 3 5 volt supply.
- GND. Ground pins.
The ATmega328 has 32 kB of flash memory for storing code (of which 0.5kB is use for the boot-loader). It has 2 kB of SRAM and 1kBs of EEPROM (which can be read and written with the EEPROM library).
Input and Output :
Each of the 14 digital pins on the Pro Mini can be use as an input or output, using pinMode(), digitalWrite(), and digitalRead() functions. They operate at 5 volts (depending on the model). Each pin can provide or receive a maximum of 40 mA and has an internal pull-up resistor (disconnected by default) of 20-50 kOhm. In addition, some pins have specialize functions :
- Serial: 0 (RX) and 1 (TX) : Use to receive (RX) and transmit (TX) TTL serial data. These pins are connect to the TX-0 and RX-1 pins of the six pin header.
- External Interrupts: 2 and 3 : These pins can be configure to trigger an interrupt on a low value, a rising or falling edge, or a change in value. See the attachInterrupt() function for details.
- PWM: 3, 5, 6, 9, 10, and 11. Provide 8-bit PWM output with the analogWrite() function.
- SPI: 10 (SS), 11 (MOSI), 12 (MISO), 13 (SCK). These pins support SPI communication, which, although provide by the underlying hardware, is not currently include in the Arduino language.
- LED: 13. There is a built-in LED connect to digital pin 13. When the pin is HIGH value, the LED is on, when the pin is LOW, it’s off.
The Pro Mini has 8 analog inputs, each of which provide 10 bits of resolution (i.e. 1024 different values). Four of them are on the headers on the edge of the board; two (inputs 4 and 5) on holes in the interior of the board. The analog inputs measure from ground to VCC. Additionally, some pins have specialize functionality:
- I2C: A4 (SDA) and A5 (SCL). Support I2C (TWI) communication using the Wire library.
- Reset. Bring this line LOW to reset the microcontroller. Typically use to add a reset button to shields which block the one on the board.
The Arduino Pro Mini has a number of facilities for communicating with a computer, another Arduino, or other microcontrollers. The ATmega328 provides UART TTL serial communication, which is available on digital pins 0 (RX) and 1 (TX). The Arduino software includes a serial monitor which allows simple textual data to be sent to and from the Arduino board via a USB connection.
A SoftwareSerial library allows for serial communication on any of the Pro Mini’s digital pins.
The ATmega328 also supports I2C (TWI) and SPI communication. The Arduino software includes a Wire library to simplify use of the I2C bus; see the reference for details. To use the SPI communication, please see the ATmega328 datasheet.
The ATmega328 on the Arduino Pro Mini comes pre-burn with a boot-loader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500 protocol. You can also bypass the boot-loader and program the ATmega328 with an external programmer; see these instructions for details.
Automatic (Software) Reset :
Rather then requiring a physical press of the reset button before an upload, the Arduino Pro Mini is design in a way that allows it to be reset by software running on a connected computer. One of the pins on the six-pin header is connect to the reset line of the ATmega328 via a 100 nF capacitor. This pin connects to one of the hardware flow control lines of the USB-to-serial converter connect to the header; RTS when using an FTDI cable.
When this line is assert (taken low), the reset line drops long enough to reset the chip. The Arduino software uses this capability to allow you to upload code by simply pressing the upload button in the Arduino environment. This means that the boot-loader can have a shorter timeout, as the lowering of the reset line can be well-coordinate with the start of the upload.
This setup has other implications. When the Pro Mini is connect to either a computer running Mac OS X or Linux, it resets each time a connection is made to it from software (via USB). For the following half-second or so, the boot-loader is running on the Pro. While it is program to ignore malformed data (i.e. anything besides an upload of new code), it will intercept the first few bytes of data sent to the board after a connection is open. If a sketch running on the board receives one-time configuration or other data when it first starts, make sure that the software with which it communicates waits a second after opening the connection and before sending this data.
Package Includes :
1 x Arduino Pro mini board.
Specifications and Features :
|Input Voltage||5 – 12 V (5V model)|
|Digital I/O Pins||14 (of which 6 provide PWM output)|
|Analog Input Pins||6|
|DC Current per I/O Pin||40 mA|
|Flash Memory||32 kB (of which 0.5 kB used by bootloader)|
|Clock Speed||8 MHz (3.3V model) or 16 MHz (5V model)|