$on and $broadcast in angular

I have a footerController and codeScannerController with different views.

angular.module('myApp').controller('footerController', ["$scope", function($scope) {}]);

angular.module('myApp').controller('codeScannerController', ["$scope", function($scope) {
console.log("start");
$scope.startScanner = function(){...

When I click on a <li> in footer.html I should get this event in codeScannerController.

<li class="button" ng-click="startScanner()">3</li>

I think it can be realised with $on and $broadcast, but I don’t know how and can’t find examples anywhere.