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Units can be daisy-chained with additional Pololu servo on a single serial line


#1

Hello,
According to the phrase on your web “Units can be daisy-chained with additional Pololu servo … on a single serial line.” How should I connect a mini maestro 12 and a mini maestro 18 so that the master control center can control 30 servos?


#2

Hello.

The Maestro Control Center can only connect to a single Maestro at a time. This means that since the Maestro with the most number of channels we have is a 24-channel Maestro, the Maestro Control Center can control at most 24 servos.

However, there are a couple things you can do to achieve control of 30 servos with a system that uses a 12-channel Maestro and 18-channel Maestro. One way is to plug each Maestro to your computer with its own USB cable, open up two instances of the Maestro Control Center, and use the drop-down box in one instance to connect to the 12-channel Maestro and in the other instance to connect to the 18-channel Maestro. Another way is to plug both Maestros into your computer with their own USB cables, open up a single instance of the Maestro Control Center, and use the drop-down box to switch between the 12 and 18-channel Maestros.

That daisy-chaining phrase describes a way to connect multiple Maestros to a computer in order to control servos via a serial interface (which is different from solely using the Maestro Control Center). You can learn more about how to make daisy-chain connections under the “Daisy Chaining” section of the Maestro’s user’s guide, which can be found under the “Resources” tab of its product page. If something in that section is confusing, please specifically describe what it is, and I would be happy to help clarify.

-Jon


#3

Thanks for your answer, my question now is how to synchronize the movements of the 2 Pololu servo so that they both run the program simultaneously. At the start,I can do a simulteneous reset but how do I guarantee that at any given time during the program runs both movements are synchronized?


#4

It is difficult to offer advice for synchronizing servo movement across both of your Maestro boards without knowing more about how you are now using each Maestro. In your first post it sounded like you might want to control your servos directly from the Maestro Control Center, or maybe use the serial interface. However, your latest post makes it seem like you might be running scripts on each of your Maestros. Can you tell me specifically how you are controlling your servos? Can you also attach the settings file for each Maestro that you are using? You can generate the settings file by clicking File > Save Settings File… from the Maestro Control Center.

-Jon


#5

Currently I do not have a project, it is in study phase since I am analyzing the feasibility of using Maestro or a SCC32 (because I need to control approx. 30 servos) to animate a robot. The idea is to program the movements through a Maestro Control Center because it is easy to use and adjust directly on the model. The Maestros need to work separately therefore my first question was how to operate 2 Maestros as if they were one (Servo 0 through 40) with the Maestro Control Center.
As you well said, I pretend to run scripts in each of the Maestro and as I move along in my project, I will be happy to share with you the questions that arise. For now you already helped me.
So far I have not planned to use the series interface because my knowledge of the Maestro is still very limited.

Jordi