The Maestro’s two virtual serial ports can be used in Linux without any special driver installation. The virtual serial
ports are managed by the cdc-acm kernel module, whose source code you can find in your kernel’s source code

drivers/usb/class/cdc-acm.c

. When you connect the Maestro to the PC, the two virtual serial ports should appear

as devices with names like

/dev/ttyACM0

and

/dev/ttyACM1

(the number depends on how many other ACM devices

you have plugged in). The port with the lower number should be the Command Port, while the port with the higher
number should be the TTL Serial Port. You can use any terminal program (such as kermit) to send and receive bytes
on those ports.

3.c. Using the Maestro without USB

It is possible to use the Maestro as a serial servo controller without installing any USB drivers or using a PC. Without
using USB, you will not be able to change the Maestro’s settings, but you can use the default settings which are
suitable for many applications. The default settings that the Maestro ships with are described below.

Default Settings

• The serial mode is “UART, detect baud rate”; after you send the 0xAA baud rate indication byte, the Maestro
will accept TTL-level serial commands on the RX line.

• The Pololu Protocol device number is 12, the Mini SSC offset is 0, and serial timeout and CRC are disabled.

• All channels are configured as servos, with a minimum pulse with of 992 μs and a maximum pulse width of
2000 μs.

Pololu Maestro Servo Controller User's Guide

3. Getting Started

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