USAGE.md

RIOT version

• use 255a5cd as earliest version for fixed duplicate address detection

Config

• Channel: DEFAULT_CHANNEL=19
• Number of display LEDs: LUKE_DISPLAY_CNT=64

Boot-up

1. Start Raspberry Pi with IEEE 802.15.4 radio connected to monitor with following services
   • lowpan
   • aiocoap-rd listening on 6LoWPAN interface generated by lowpan service
   • nginx pointing root to ./webfrontend
   • [./coap_service/coap_service.py] with aiocoap-rd address and configured root of nginx
2. start dino
3. start controller
4. start display
5. if all nodes appear in the web frontend the demo is basically set-up
6. Drag nodes around to set their targets

Troubleshooting

Widget is not movable anymore

• reload page (button is supposed to at one point)

Node widget does not appear

• reset node manually
• if it still does not appear: reboot the whole demo (red button top right). Wait until the page refreshes (may take several seconds) then reset the node manually

Point counter in web frontend does not react

• ¯\_(ツ)_/¯... Reboot demo?

Difficulty

• Difficulty (= decrement interval) can be set with the SWD0 button of th SAMR21-XPRO of the display
• LEDs will show the new difficulty level (the more LEDs the more difficult)
• Default difficulty is 9 of 10

Details

Background

• The demo is based on CoAP and CoRE-RD
• Nodes have to register their resources with the resource directory
• Nodes identify themselves to the frontend using a section of their path <id>
  • /dino => dino
  • /btn => controller
  • /dsp => display
• To configure the target of an action (button pressed, game won, ...) a node needs to have a POST-able target /<id>/target
  • Expects a JSON object with:
    • addr: the address + port (optional) part of a CoAP-URL (e.g. [2001:db8::1] or [2001:db8::2]:5678) as string
    • path: the path part of a CoAP-URL (e.g. /dsp/points) as string
  • The configured target needs to be able to handle POSTed JSON objects with:
    • points: an integer
  • The frontend expects those targets to be of the format /<id>/points
• All nodes should have a POST-able resource /reboot to reboot the node

Current setup

Currently the demo has 3 nodes

controller

• Resources:
  • /btn/target (POST / GET) (see Background):
    • GET: currently configured target
    • POST: configures target of the button
  • /reboot (POST): reboots the node
• Sends a POST request to its configured target every 100ms
  • points will be the number of button presses since the last POST request

display

• Resources:
  • /dsp/points (POST / GET):
    • GET (observable): JSON object with
      • points: current points counter as integer
    • POST: Expects JSON object with
      • points: number of points to increment points counter
  • /dsp/target (POST / GET) (see Background)
    • GET: currently configured target
    • POST: configures target of the button
  • /reboot (POST): reboots the node
• Sends a POST request to its configured target on victory condition (5 times received to /dsp/points to get points counter to the maximum)
  • points will be the current points counter as integer

dino

• Resources:
  • /dino/points (POST): JSON object with
    • points: integer, if > 0 the dino moves
  • /reboot (POST): reboots the node

Extending the demo

Adding a node

• make sure they follow the parameters set in Background
• extend get_node_name() in webfrontend/js/luke.js with the identifying URL part
• add new node name to NODES_ORDERED in webfrondend/js/luke.js
• create a <node_name>.html.part representing the widget in webfrontend/js/luke.js

Adding new resources

• extend get_resource_name() in webfrontend/js/luke.js
• extend if necessary: get_handlers, obs_handlers, post_handlers in webfrontend/js/luke.js
• add capability for custom POST success handlers to CoAPResource.post() if necessary