Hi,
I have spent the last 2 days figuring this one out but have tried all in my capacity.
The Teensy 4.0 usb serial seems to be broken on Ubuntu 20.04. I am trying to setup some T4s as ROS serial nodes in a larger project, on ROS1 so I must use 20.04. I have 00-rules installed and disabled the modemmanager, tried forcing USB2, USB3, with/without a hub, no difference, the usb serial connection is unstable at best and if writing anything from host to T4 the serial socket hangs and I can only quit by physically disconnecting the board. I have tried the while(!Serial) trick, and pretty much tried any smallest suggestion in all posts.
This morning I tried swapping for a Teensy LC and it runs flawlessly on the exact same setup and code.. so there is something to do with the T4 usb serial stack. Steps to reproduce, pretty much any barebone Serial.begin/read/print() and writing/reading from pyserial shows the issue. I tried on 18.04 a barebone read/write loop and it works fine.
Problem is I need the compute power of the T4 so the LC is really not going to cut it.. and I purchased quite a bunch.. Any idea where to look else?
Thibault
I have spent the last 2 days figuring this one out but have tried all in my capacity.
The Teensy 4.0 usb serial seems to be broken on Ubuntu 20.04. I am trying to setup some T4s as ROS serial nodes in a larger project, on ROS1 so I must use 20.04. I have 00-rules installed and disabled the modemmanager, tried forcing USB2, USB3, with/without a hub, no difference, the usb serial connection is unstable at best and if writing anything from host to T4 the serial socket hangs and I can only quit by physically disconnecting the board. I have tried the while(!Serial) trick, and pretty much tried any smallest suggestion in all posts.
This morning I tried swapping for a Teensy LC and it runs flawlessly on the exact same setup and code.. so there is something to do with the T4 usb serial stack. Steps to reproduce, pretty much any barebone Serial.begin/read/print() and writing/reading from pyserial shows the issue. I tried on 18.04 a barebone read/write loop and it works fine.
Problem is I need the compute power of the T4 so the LC is really not going to cut it.. and I purchased quite a bunch.. Any idea where to look else?
Thibault