Pololu Mini Maestro Series User manual

Mini Maestro 24-Channel USB Servo Controller (Partial Kit)
Getting started with the Maestro Servo Controller
Overview
Maestro family of USB servo controllers: Mini 24,
Mini 18, Mini 12, and Micro 6.
The Mini Maestros are the newest of Pololu’s second-generation USB servo controllers, offering
more channels and features than the smaller six-channel Micro Maestro. The Mini Maestros are
available in three sizes, and they can be purchased fully assembled or as partial kits:
Mini Maestro 12 — fully assembled
Mini Maestro 12 — partial kit
Mini Maestro 18 — fully assembled
Mini Maestro 18 — partial kit
Mini Maestro 24 — fully assembled
Mini Maestro 24 — partial kit
The Mini Maestros are highly versatile (and compact) servo controllers and general-purpose I/O
boards. They support three control methods: USB for direct connection to a computer, TTL serial
for use with embedded systems, and internal scripting for self-contained, host controller-free
applications. The channels can be configured as servo outputs for use with radio control (RC)
servos or electronic speed controls (ESCs), as digital outputs, or as analog/digital inputs. The
extremely precise, high-resolution servo pulses have a jitter of less than 200 ns, making these
servo controllers well suited for high-performance applications such as robotics and animatronics,
and built-in speed and acceleration control for each channel make it easy to achieve smooth,
seamless movements without requiring the control source to constantly compute and stream
intermediate position updates to the Mini Maestros. The Mini Maestros also feature configurable
pulse rates from 1 to 333 Hz and can generate a wide range of pulses, allowing maximum
responsiveness and range from modern servos. Units can be daisy-chained with additional Pololu
servo and motor controllers on a single serial line.

The Status tab in the Maestro Control Center.
A free configuration and control program is available for Windows and Linux, making it simple to
configure and test the device over USB, create sequences of servo movements for animatronics or
walking robots, and write, step through, and run scripts stored in the servo controller. The Mini
Maestros’ 8 KB of internal script memory allows storage of up to approximately 3000 servo
positions that can be automatically played back without any computer or external microcontroller
connected.
Because the Mini Maestros’ channels can also be used as general-purpose digital outputs and
analog or digital inputs, they provide an easy way to read sensors and control peripherals directly
from a PC over USB, and these channels can be used with the scripting system to enable creation
of self-contained animatronic displays that respond to external stimuli and trigger additional events
beyond just moving servos.
The fully assembled versions of the Mini Maestro ship with 0.1″ male header pins installed as
shown in the respective product pictures. The partial kit versions ship with these header pins
included but unsoldered, which allows the use of different gender connectors or wires to be
soldered directly to the pads for lighter, more compact installations. A USB A to mini-B cable (not
included) is required to connect this device to a computer. The Micro and Mini Maestros have

0.086″ diameter mounting holes that work with #2 and M2 screws.
Micro Maestro 6-channel USB servo
controller (fully assembled) controlling
three servos.
Main Features
Three control methods: USB, TTL (5V) serial, and internal scripting
0.25µs output pulse width resolution (corresponds to approximately 0.025° for a
typical servo, which is beyond what the servo could resolve)
Pulse rate configurable from 1 to 333 Hz (2)
Wide pulse range of 64 to 4080 µs (2)
Individual speed and acceleration control for each channel
Channels can be optionally configured to go to a specified position or turn off on
startup or error
Alternate channel functions allow the channels to be used as:
General-purpose digital outputs (0 or 5 V)
Analog or digital inputs (channels 0 – 11 can be analog inputs; channels 12+ can
be digital inputs)
One channel can be a PWM output with frequency from 2.93 kHz to 12 MHz and
up to 10 bits of resolution
A simple scripting language lets you program the controller to perform complex
actions even after its USB and serial connections are removed
Comprehensive user’s guide
The Channel Settings tab in the Maestro
Control Center.
Free configuration and control application for Windows and Linux makes it easy to:
Configure and test your controller
Create, run, and save sequences of servo movements for animatronics and
walking robots
Write, step through, and run scripts stored in the servo controller
Two ways to write software to control the Maestro from a PC:

Virtual COM port makes it easy to send serial commands from any development
environment that supports serial communication
Pololu USB Software Development Kit allows use of more advanced native USB
commands and includes example code in C#, Visual Basic .NET, and Visual C++
TTL serial features:
Supports 300 – 200,000 bps in fixed-baud mode, 300 – 115,200 bps in autodetect-
baud mode (2)
Simultaneously supports the Pololu protocol, which gives access to advanced
functionality, and the simpler Scott Edwards MiniSSC II protocol (there is no need
to configure the device for a particular protocol mode)
Can be daisy-chained with other Pololu servo and motor controllers using a
single serial transmit line
Chain input allows reception of data from multiple Mini Maestros using a single
serial receive line without extra components (does not apply to Micro Maestros)
Can function as a general-purpose USB-to-TTL serial adapter for projects
controlled from a PC
Board can be powered off of USB or a 5 – 16 V battery, and it makes the regulated 5V
available to the user
Upgradable firmware
Maestro Comparison Table
Micro
Maestro
Mini
Maestro 12
Mini
Maestro 18
Mini
Maestro 24
Channels: 6 12 18 24
Analog input
channels: 6 12 12 12
Digital input channels: 0 0 6 12
Width: 0.85"
(2.16 cm)
1.10"
(2.79 cm)
1.10"
(2.79 cm)
1.10"
(2.79 cm)
Length: 1.20"
(3.05 cm)
1.42"
(3.61 cm)
1.80"
(4.57 cm)
2.30"
(5.84 cm)
Weight(1): 3.0 g 4.2 g 4.9 g 6.0 g
Configurable pulse
rate(2): 33–100 Hz 1–333 Hz 1–333 Hz 1–333 Hz
Pulse range(2): 64–3280 µs 64–4080 µs 64–4080 µs 64–4080 µs
Script size(3): 1 KB 8 KB 8 KB 8 KB
1 This is the weight of the board without header pins or terminal blocks. 2 The available pulse rate
and range depend on each other and factors such as baud rate and number of channels used. See
the Maestro User’s Guide for details. 3 The user script system is more powerful on the Mini
Maestro than on the Micro Maestro. See See the Maestro User’s Guide for details.
Application Examples and Videos

Micro Maestro as the brains of a tiny
hexapod robot.
Serial servo controller for multi-servo projects (e.g. robot arms, animatronics, fun-
house displays) based on microcontroller boards such as the BASIC Stamp, Orangutan
robot controllers, or Arduino platforms
Computer-based servo control over USB port
Computer interface for sensors and other electronics:
Read a gyro or accelerometer from a computer for novel user interfaces
Control a string of ShiftBrites from a computer for mood lighting
General I/O expansion for microcontroller projects
Programmable, self-contained Halloween or Christmas display controller that
responds to sensors
Self-contained servo tester
An example setup using a Micro Maestro to control a ShiftBar and Satellite LED Module is shown
in the picture below and one of the videos above. Maestro source code to control a ShiftBar or
ShiftBrite is available in the Example scripts section of the Maestro User’s guide.
Connecting the Micro Maestro to a chain of ShiftBars. A single 12V
supply powers all of the devices.
Documentation on producer website.