Failing to compile NeoTrellisM4 example code in Arduino ("Serial1" not declared in this scope...)

[dgately]

Attempting to compile Arduino code that uses the Adafruit_NeoTrellisM4 library results in multiple errors claiming "Serial1" not declared in this scope...

macOS: 10.14.5 Arduino IDE: 1.8.9 Adafruit NeoTrellis M4 Library: 1.1.2 Board: Adafruit Neo Trellis M4 (SAMD51)

error: ... /.../Documents/Arduino/libraries/Adafruit_NeoTrellisM4/Adafruit_NeoTrellisM4.cpp:89:5: error: 'Serial1' was not declared in this scope Serial1.begin(31250); ...

Arduino error report is attached. TrellisErrors.txt

The error shows up within the Neo Pixel M4 library code as can be reviewed in the attached compiler error log. This error shows up when compiling any of the examples as well as the source from: [url]https://learn.adafruit.com/trellis-m4-midi-keypad-and-tilt-controller/code-in-arduino[/url]. My assumption is that this is a library issue, possibly a conflict between whatever libraries I've loaded and what Adafruit's Neo Pixel M4 library requires.

Note: Each of the required latest Adafruit libraries have been loaded.

Example tested: https://learn.adafruit.com/trellis-m4-midi-keypad-and-tilt-controller/code-in-arduino