gpeipman/windowsiottrafficlights

Traffic lights simulator built on Windows 10 IoT Core and RaspberryPi. Implementations for Windows 10 IoT Core background task and UWP appliation.

WindowsIotTrafficLights

Traffic lights simulator built on Windows 10 IoT Core and Raspberry Pi. It supports loading of LED blinking schedules from remote sources and switches schedules automatically. Schedule switch is controlled by timer thread that polls remote machine for new schedule. Sample contains two schedules: normal traffic lights working cycle and blinking yellow.

Electronic components

This is all you need to get things done on hardware size:

• Raspberry Pi
• Cheap breadboard
• Red, yellow and green LED
• Three resistors (I have 270Ω)
• Jumper wires for cabling

If you are not electronics guy then I suggest you to ask correct resistors for LED-s you are buying from electronics shop.

Wiring

Wiring is simple using breadboard. Just connect everything you have like shown on the following diagram.

Architecture of solution

The solution is made of three projects:

• WindowsIotTrafficLights - interfaces and their default implementations.
• WindowsIotTrafficLightsApp - UWP traffic lights app for Raspberry, has UI with traffic lights.
• WindowsIotTrafficLightsService - traffic lights implemented as Windows 10 IoT Core background task.

The core of traffic lights is shown on the following diagram.

Interfaces:

• IScheduleUpdateClient - used for LED-s schedule updates.
• ISwitcher - used to show traffic lights (be it LED-s or something else).

Classes:

• WebScheduleUpdateClient - schedule updater that requests data from web address.
• LightsManager - turns traffic lights on and off based on schedule.
• Schedule - DTO class for schedule.
• ScheduleItem - DTO class for schedule item.
• LedSwitcher - ISwitcher implementation for LED-s connected to Raspberry Pi.
• FromSwitcher - ISwitcher to bling traffic lights shapes on XAML form.
• EventBasedSwitched - Common switcher that fires ItemSwitched event when new ScheduleItem is set by manager.

Traffic lights schedule

Part of external files folder of solution is simple PHP script that selects randomly between two JSON files:

• yellow.json - blinks yellow light (traffic lights are turned off)
• traffic.json - simple traffic lights cycle

By default the script is called from my web site. If you want to change the logic of schedule update then you can copy the script and json-files to your own web server or build your own end-point (just give the address of end-point to constructor of WebScheduleUpdateClient).