GetDeviceVersion response mismatch


#1

Hello. I have followed the steps shown via How to communicate to dobot using raw protocol and referenced the latest version of the Dobot Communications Protocol that I can find on the web (v1.0.4 dated 2016/12/20). Can you please explain why a request to GetDeviceVersion returns a message with 20 bytes instead of the 9 bytes (header + length + payload + checksum) documented v1.0.4 manual?

Message sent: AA AA 02 02 00 FE
Message received: AA AA 10 02 00 03 03 00 45 31 37 30 38 31 36 31 37 32 31 B1

What are the additional bytes representing?


#2

The official websitehttps://www.dobot.cc/downloadcenter.html?sub_cat=72#sub-download already has the latest Dobot Communications Protocol (V1.1.3 dated 2018/11/27)and hopes to help you.
Thanks and best regards.


#3

Thanks @Daniel.Deng. The v1.1.3 manual shows the GetDeviceVersion response command packet as a 9 byte message (2 byte header, 1 byte length, 5 byte payload, 1 byte checksum).

The response message I receive gives a version number of 3.3.0, but there are 11 additional bytes in the message.

AA AA = Header
10 = Payload Length (16)
02 00 03 03 00 45 31 37 30 38 31 36 31 37 32 31 = Payload
B1 = Checksum

The payload being:
02 = Message ID
00 = Read, Immediate
03 = Major Version (uint8)
03 = Minor Version (uint8)
00 = Revision (uint8)
45 31 37 30 38 31 36 31 37 32 31 = unknown

What do these “unknown” bytes in the payload mean?