Here is a second beta test for Teensyduino 1.49.
EDIT: links removed, please use 1.49-beta3
Changes since Teensyduino 1.49-beta1
Add Teensy 4.0 USB MIDI, Keyboard, Mouse, Joystick
Support for MacOS Catalina
Port WS2812Serial to Teensy 4.0 (KurtE)
AVR register emulation on Teensy 4.0 (KurtE)
Fix serial DMA def on Teensy 4.0 (KurtE)
Improve ADC & XBAR defs on Teensy 4.0 (KurtE)
Improve quadrature encoder defs on Teensy 4.0 (mjs513)
Add Teensy 4.0 USB Touchscreen, not finished... work in progress
Remove serial monitor debug messages on Arduino 1.8.9
EDIT: links removed, please use 1.49-beta3
Changes since Teensyduino 1.49-beta1
Add Teensy 4.0 USB MIDI, Keyboard, Mouse, Joystick
Support for MacOS Catalina
Port WS2812Serial to Teensy 4.0 (KurtE)
AVR register emulation on Teensy 4.0 (KurtE)
Fix serial DMA def on Teensy 4.0 (KurtE)
Improve ADC & XBAR defs on Teensy 4.0 (KurtE)
Improve quadrature encoder defs on Teensy 4.0 (mjs513)
Add Teensy 4.0 USB Touchscreen, not finished... work in progress
Remove serial monitor debug messages on Arduino 1.8.9