Introduction to Arduino - Arduino Sketches: Tools and Techniques for Programming Wizardry - page 16

Arduino Pro
The Arduino Pro exists in two versions, based either on the ATmega168 or
the ATmega328. The 168 version operates at 3.3 V with an 8 MHz clock, and
the 328 version runs on 5 V at 16 MHz. Both versions have 14 digital inputs/
outputs and 6 analog inputs. It has a JST battery power connector, a power
switch to select between power modes, and space reserved for a power jack,
if needed. It does not have a USB connector but instead uses a FTDI cable for
programming.
The Arduino Pro is different from most other Arduinos in that while it is
a prototyping board it is designed to be embedded in projects. It does not
come with headers—indeed, it does not have any headers at all, as shown in
Figure 1-11. All the digital and analog inputs and outputs are placed at the
exterior of the board, retaining shield layout, ready to be soldered to wire or
connectors if necessary. Instead of being used for prototyping, the Arduino
Pro is aimed at semipermanent installation in i nished products. The Arduino
Pro was not designed by Arduino but was designed and is manufactured by
SparkFun Electronics.
Arduino Robot
The Arduino Robot is, simply put, an Arduino on wheels. There are two Arduino
boards on the Robot—one controls the on-board motors, and the other contains
sensors. The Control board controls the Motor board and gives it instructions
on how to operate.
The Control board is powered by an ATmega32u4, with 32 KB of l ash, 2.5 KB
of SRAM, and 1 KB of EEPROM. It also has an external I2C EEPROM device,
providing more storage. It has a compass, a speaker, three LEDs, a i ve-button
key pad, and an LCD screen. It also has three solder points for external I2C
devices. It also has I/O capability, with i ve digital I/Os, six PWMs, and four
analog inputs. There is space for eight analog inputs (for distance sensors,
ultrasound sensors, or other sensors) and six digital I/O pins for other devices
(four of which can be used for analog input).
The Motor board is a fully independent board, powered by an ATmega32u4,
the same microcontroller as on the Control board. The Motor board contains
two wheels powered independently, i ve IR sensors, and I2C and SPI ports. It
also contains the power supply; it is powered by four rechargeable AA batter-
ies, and contains a jack port to recharge the on-board batteries. The board can
also be powered by an on-board USB connector, but in this coni guration, for
safety reasons, the motors are disabled (Figure 1-12).