Arduino Mega Not Controlling Maestro 12

After loading the example basic code only the red light flashes. The servos do not move. The Arduino Blink example works and the Maestro Control Panel operated the Mini.

Made the setting changes/applied in the Control Panel - UART, fixed base rate, Baud rate: 9600, CRC disabled
Changed the code to reflect the Mini rather than the Micro
Wired gnd to end between the boards
Connected Maestro’s RX to Mega’s TX - pin 18
Connected Maestro’s TX to Mega’s RX - pin 19
Changed the code to reflect the RX and TX pins

Any suggestions would be appreciated.

/* This example shows how to control a single servo on a Maestro
servo controller using the PololuMaestro library. It assumes you
have an RC hobby servo connected on channel 0 of your Maestro,
and that you have already used the Maestro Control Center
software to verify that the servo is powered correctly and moves
when you command it to from the Maestro Control Center.

Before using this example, you should go to the Serial Settings
tab in the Maestro Control Center and apply these settings:

* Serial mode: UART, fixed baud rate
* Baud rate: 9600
* CRC disabled

Be sure to click "Apply Settings" after making any changes.

This example also assumes you have connected your Arduino to your
Maestro appropriately. If you have not done so, please see for more details on how
to make the connection between your Arduino and your Maestro. */

#include <PololuMaestro.h>

/* On boards with a hardware serial port available for use, use
that port to communicate with the Maestro. For other boards,
create a SoftwareSerial object using pin 10 to receive (RX) and
pin 11 to transmit (TX). */
  #define maestroSerial SERIAL_PORT_HARDWARE_OPEN
  #include <SoftwareSerial.h>
  SoftwareSerial maestroSerial(19, 18);

/* Next, create a Maestro object using the serial port.

Uncomment one of MicroMaestro or MiniMaestro below depending
on which one you have. */
//MicroMaestro maestro(maestroSerial);
MiniMaestro maestro(maestroSerial);

void setup()
  // Set the serial baud rate.

void loop()
  /* setTarget takes the channel number you want to control, and
     the target position in units of 1/4 microseconds. A typical
     RC hobby servo responds to pulses between 1 ms (4000) and 2
     ms (8000). */

  // Set the target of channel 0 to 1500 us, and wait 2 seconds.
  maestro.setTarget(0, 6000);

  // Set the target of channel 0 to 1750 us, and wait 2 seconds.
  maestro.setTarget(0, 7000);

  // Set the target of channel 0 to 1250 us, and wait 2 seconds.
  maestro.setTarget(0, 5000);


I am sorry you are having problems controlling your Maestro from an Arduino. Thank you for posting the code you are using. Can you post pictures of your setup that show all of your connections? Additionally, can you post your Maestro settings file? You can save your Maestro settings file by choosing the “Save settings file…” option within the “File” drop-down menu in the Maestro Control Center software.

The red LED is the error indicator LED. Can you try connecting your Maestro to the Maestro Control Center while your code is running and checking the “Errors” tab to see which errors are being triggered?



With the program loaded into the Mega, the results were the same, no movement of the servo. However, as soon as I plugged in the cable to get the error messages from the Maestro Control Panel the servos started running the program properly. When the cable was disconnected, the servos stopped. There were no error messages in the Maestro control panel.

Hopefully you can understand the wiring from the three pictures. I used some rc servo extensions and clipped the unused wires off them. The black gnd wire is the best example.’


Archiving built core.docx (99.1 KB)

maestro_settings.txt (2.49 KB)

I do not see any power connections for the Arduino or the Maestro in your pictures, but it sounds like you are not supplying power to the logic side of the Maestro board when you are running your system. Please note that the Maestro is not powered from the servo power rail by default. There are a couple options for supplying power detailed in the “Powering the Maestro” section of the Maestro user’s guide. If you continue having problems, can you post updated pictures that include all of your power connections?



Thanks for the help. When I took the pictures, it wasn’t hook up to the computer, thus the USB connection to the Mega wasn’t visible. In the second picture, at the bottom is the blue colored battery providing power to the servos. I totally missed the fact that power had to be added to the logic side of the Maestro. I will add that later today and let you know the results.



Got it working. I moved the jumper so the logic side could be powered by the servo battery.

Thanks for the help.