fix calculation of subsecond conversion in MIX or BIN mode #264

	name: STM32RTC Continuous Integration
	on:
	push:
	branches:
	- main
	paths-ignore:
	- '*'
	- '**.md'
	- '**.txt'
	pull_request:
	paths-ignore:
	- '*'
	- '**.md'
	- '**.txt'
	# Allows you to run this workflow manually from the Actions tab
	workflow_dispatch:
	jobs:
	lib_build:
	runs-on: ubuntu-latest
	name: Library compilation
	steps:
	# First of all, clone the repo using the checkout action.
	- name: Checkout
	uses: actions/checkout@main

	- name: Compilation
	id: Compile
	uses: stm32duino/actions/compile-examples@main
	with:
	custom-config: "./extras/rtc_cores_config.json"

	# Use the output from the `Compile` step
	- name: Compilation Errors
	if: failure()
	run: \|
	cat ${{ steps.Compile.outputs.compile-result }}
	exit 1

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