Added support for Teensy 4.0 and 4.1

[Lauszus]

Fixes #529, fixes #560

[Lauszus]

I've also replaced Travis with Github Actions, as Travis was painfully slow to even start the jobs.

[unitbob1]

To confirm, does this enable the use of the Teensy 4.1 natively, using the USB headers found on top of the board, or using the external USB host shield?

[Lauszus]

@unitbob1 this is for using the USB host shield only. If you want to use the native interface, then check out this library: https://github.com/PaulStoffregen/USBHost_t36

[xxxajk]

...or uhs3, which still needs a tid-bit of work, but should support it just fine.

[shift838]

Even with this latest code to add support for Teensy 4.0 and 4.1 I still cannot get this my code compiled. It compiles under Teensy 3.2 but not 4.0 or 4.1

I get the below error:

#error "Please define board in avrpins.h"

[xxxajk]

Native interface is also supported under UHS30

[shift838]

would this require code changes or is UHS30 backwards compatible to 2.0 syntax?

[xxxajk]

It is mostly compatible. Many things are changed for the better.
Examples:

You don't have to constantly poll the USB, because it operates in the background once started.

You define in the sketch what you want to use

Interfaces are unified, e.g. USB serial convertors are all treated the same.

...and much more

[shift838]

i uninstalled the Arduino IDE and reinstalled.

in 2.0 when I compile for Teensy 3.2 i would use the below include statements:

#include <hidboot.h>
#include <usbhub.h>

Is there any docs to explain the new UHS 3.0 ?

What would replace those include statements.

I have tried

#include <UHS_HIDRAWBOOT_KEYBOARD.h>
#include <UHS_HUB.h>

but get :

fatal error: UHS_HIDRAWBOOT_KEYBOARD.h: No such file or directory

[xxxajk]

You use defines, not includes. See the examples.