No response to fast sync read command with Dynamixel MX28-AR

I have 2 Dynamixel MX28-AR motors controlled by a Teensy 4.1 with RS485 communication to the servos over the 2.0 protocol. Servos are powered from a 12V wall adapter. Reading and writing individually works fine, as does sync write operations. Whenever I try to syn read though, the servos do not send a response. I have reproduced the issue with the servos connected to a computer with the U2D2 adapter and the Dynamixel Wizard software, so that’s what I’ll show here.

In the dynamixel wizard I can connect to the daisy-chained servos fine (1Mbps baud). In the “Packet” toolbox, you can see that reading from both servos (IDs 1 and 2) is fine, but there is no response to my fast sync read command.

Here is the current configuration (same for both):

Any thoughts on why fast sync read does not respond? Is this supported in these servos or are there some settings I have to change to allow for fast sync reads?



Hi @wflan

Unfortunately, the DYNAMIXEL MX series (2.0 Firmware) does not function the Fast Sync / Bulk read / write instruction (DYNAMIXEL X Series only).

  • I will add a note to e-Manual about Fast Sync with MX-28/64/106 (2.0)

Sorry for your inconvenience,

Thank you,

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