I decided to plug the XL-320n used to articulate the hands of Poppy on the same network as the upper body network.
Unfortunately, I cannot start the robot. (there is not message error)
How do I specify XL-320 motors in this configuration ? do you have a simple example of json ?
Actually we never really tested if this could work or not. I’m tempted to say that the protocol v1 and v2 are not compatible and that it would not work. I hope I’m wrong there!
From pypot point of view, i guess it would be feasible but it’s not that easy to do. It would require to modify how the DxlIO and Dxl320IO are working to have some meta-class on top which open once the port and can send/received messages using both protocols.
Yet, once again we never tested this and I would be really interested to get some feedback! I’ve written a test example: https://gist.github.com/1264cc525a4b10d0d4e7
I do not have a setup with both motors type on the same bus so I could not test. Let me know what you get!
I tried the code you did send and I confirm it does not work for the moment. As I have no time to enhance pypot to manage this configuration, I came back to the old conf with a specific USB2AX for XL-320.
Talking Dxl 1.0 and Dxl 2.0 on the same bus is not a problem in itself: Dxl1.0 commands are ignored by 2.0 devices as incorrect (wrong header) and Dxl 2.0 commands are ignored by 1.0 devices as they look like commands sent to ID 0xFD - and/or because the checksum is invalid.
However, it is important to note that USB2AX units made until the beginning of 2014 (released long before Dxl 2.0 existed) had a firmware with a bug that would crash when a Dxl 2.0 command was sent.
See http://www.xevelabs.com/doku.php?id=product:usb2ax:firmware_update if you have an USB2AX bought before mid-2014 to fix that.
One very direct way to check if you have this problem (if you have a Windows machine…) is to run the Dynamixel Wizard of RoboPlus v1.x.x, and to run a search (regardless of what is connected to the USB2AX). A units with the old firmware will freeze the app (frozen at the first ping), while newer versions will quickly go through the pings to each ID.
Now for the the specifics of the XL-320: be careful, they do not like 12V (they are rated for 7.4V). Putting them on the same data bus is fine but power should be adapted, either with a different power source or a DC/DC regulator.
At 12V they will work for some time (we did that with our Mikata humanoid at RobotWorld at the ends of last year) but might burn easily (we burnt 2 or 3 iirc).
One failure mode of a burnt servo is to make communication on the bus it is connected to impossible.
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