Add xon_xoff enable/disable, bump version #39

	# This is a basic workflow to help you get started with Actions

	name: Build Firmware

	# Controls when the workflow will run
	on:
	# Triggers the workflow on push or pull request events but only for the develop branch
	push:
	paths:
	- 'microfw/**'
	- '.github/workflows/build_sam3u_fw.yaml'

	pull_request:
	paths:
	- 'microfw/**'
	- '.github/workflows/build_sam3u_fw.yaml'


	# A workflow run is made up of one or more jobs that can run sequentially or in parallel
	jobs:
	fwbuild:
	# The type of runner that the job will run on
	name: Build all firmware to make sure compilation works
	runs-on: ubuntu-latest

	# Steps represent a sequence of tasks that will be executed as part of the job
	steps:
	# Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
	- uses: actions/checkout@v2
	- name: Install compilers
	run: >-
	sudo apt install -y make build-essential gcc-arm-none-eabi
	- name: Build CW340 firmware
	run: \|
	cd microfw/CW310/src
	git submodule update --init naeusb
	make TARGET=CW340 -j
	- name: Build CW310 firmware
	run: \|
	cd microfw/CW310/src
	git submodule update --init naeusb
	make TARGET=CW310 -j

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