OK, the penny has finally dropped! This clears up the mystery for me. I understood what you put in your original post but it didn't fully register. I certainly don't need microsecond timing for this, I just thought...
Thanks for all the responses. Some useful pointers but maybe I should clarify a couple of things. First the title of my post might be misleading, it obviously isn't a performance issue but perhaps an implementation...
I'm starting a new project that will be using a Teensy 4.0 or 4.1, but I haven't ordered it yet, so I'm prototyping some concepts on an ATmega328 based SparkFun RedBoard. I'm simply testing interrupt code from a limit...
Thanks Paul! Can confirm the new 1.54-beta6c version is now quicker than a quick thing.
Edit: Beta version installed on machine in OP. Just checked the new HP in my shop and the original loader version 1.53 loads...
I have trouble with GTK2/3 compatibility all the time and usually have to install additional libraries. I just found out about lack of 32bit support when I tried to upgrade my shop PC. It's impossible to keep up to...
I'm happy to help with any testing. In addition to the machine in my OP I have a new HP All-in-one that I just set up to dual boot Windows and Ubuntu 20.04. I have loaded Teensyduino on it but not yet tested it. I...