User Manual

The USB Chained serial mode.

The UART serial mode.

opening the TTL Port determines the baud rate used to receive and send bytes on RX and TX. This

allows your computer to control the Maestro and simultaneously use the RX and TX lines as a general

purpose serial port that can communicate with other types of TTL serial devices.

USB Chained: In this mode, the

Command Port is used to both transmit

bytes on the TX line and send

commands to the Maestro. The

Maestro’s responses to those

commands will be sent to the Command

Port but not the TX line. Bytes received

on the RX line will be sent to the

Command Port but will not be interpreted

as command bytes by the Maestro. The

baud rate you set in your terminal program when opening the Command Port determines the baud

rate used to receive and send bytes on RX and TX. The TTL Port is not used. This mode allows a

single COM port on your computer to control multiple Maestros, or a Maestro and other devices that

have a compatible protocol.

UART: In this mode, the TX and RX lines

can be used to send commands to the

Maestro and receive responses from it.

Any byte received on RX will be sent to the

Command Port, but bytes sent from the

Command Port will be ignored. The TTL

Port is not used. The baud rate on TX and

RX can either be automatically detected by

the Maestro when a 0xAA byte is received

on RX, or it can be set to a fixed value specified in bits per second (bps). This mode allows you to

control the Maestro (and send bytes to a serial program on the computer) using a microcontroller or

other TTL serial device.

Other serial settings:

Enable CRC: If checked, the Maestro will require a cyclic redundancy check (CRC) byte at the end of

every serial command except the Mini SSC command (see Section 5.d).

Device Number: This is the device number (0–127) that is used to address this device in Pololu

Protocol commands. This setting is useful when using the Maestro with other devices in a daisy-

chained configuration (see Section 5.g).

5. Serial Interface Page 48 of 102