Micro maestro with a twist

Hi!
Would it be possible to have the micro maestro work in paralell with another serial device (with same baudrate) using the ttl port?
See the crude drawing for a better description:)

-digmeup-

Yes, what you are asking for is possible, but your current wiring diagram will not work.

The Maestro’s TX line is an output that is always being driven, even if no data is being sent, so you can not directly connect it to the TX line of your other TTL serial device. Do you need to be able to receive data from both the Maestro and the other device? If so, you would have to buy an AND gate and use it so to implement XBeeRX = MaestroTX & OtherTX.

Alternatively, you could get the 12-channel Mini Maestro which has an AND gate built in to it for exactly this purpose. If you got the 12-channel Mini Maestro, your wiring would look like this picture from the Maestro user’s guide:

where the first (left-most) block is your XBEE, the second block is your Mini Maestro 12, and the third block is your other TTL serial device.

Also, are you able to program the other TTL serial device? You need to make sure that commands you send to the Maestro don’t cause unintended operations on your other device, and vice-versa. If your other TTL serial device is a user-programmable microcontroller, you could make it follow the Pololu Protocol and assign it a device number that is not the same as your Maestro’s device number.

You should read the chaining section of the Maestro user’s guide for more information.

As always, remember to connect the Grounds of all three devices.

–David