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c-beam MQTT

MQTT is a machine-to-machine (M2M)/“Internet of Things” connectivity protocol. see:

We are running a mqtt server on on port 1883. It's only reachable from the internal network.

An up-to-date listing of artefacts and their topics can be found from

The content of the current participant folder (updated by running a grunt createMarkup command in c-flo)

component source label inports outports
c-base/ampel-nerd n/a pedestrian traffic light in front of the door to nerdareacolors, n/a
c-base/barstatus-bar n/a c-base bar status sign at the barbarstatus, n/a
c-base/barstatus-c-lab n/a c-base bar status sign in the c-labbarstatus, n/a
c-base/barstatus-nerd n/a c-base bar status sign in the nerd areabarstatus, n/a
c-base/c-beam on-board computer n/a userboarding,usereta,playsound,playrandomsound,saytext,openurl1,openurl2,time,barstatus,
c-base/c_leuse n/a c-base airlockplaysound,playrandomsound,saytext, n/a
c-base/he1 n/a c-base siri data rescue probeopenurl, n/a
c-base/ingress-table Table n/a cbase,
c-base/mechblast n/a c-base workshop blasterplaysound,playrandomsound,saytext, n/a
c-base/nerdctrl n/a c-base nerd control interfaceopenurl,playsound,playrandomsound,saytext,openurl,
c-base/siri n/a c-base siri data rescue probeopenurl,playsound,playrandomsound,saytext,openurl,

Currently there are the following topics:

topic interval description
info/time 1 minute current date and time
c_out/loop 10 minutes starts a new sound loop on c_out
c_out/play n/a playload plays various sound samples
c_out/Julia n/a playload plays announcements on c_out via tts with voice Julia
nerdctrl/open n/a opens the payload URL in a browser in the nerdarea
client/echelon n/a this is a retained topic, if it is available, the traffic stats script on echelon is running
system/echelon/traffic 1 minute average incoming and outgoing traffic on ipb and kdg lines from echelon in bytes/s since last message
ingress/status/+ n/a these are retained topics and show status of the ingres portals around the c-base
user/boarding n/a triggered when a member logs in, message contains the username in JSON format
ampel/nerd n/a Beispiel JSON-Daten für die Message: '{“red”: 1, “green”: 0}'
ampel/mainhall n/a wie, ampel nerd, aber zusätzlich noch mit Gelb: {“red”: 1, “green”: 1, “yellow”: 1}


The topics from echelon are published with a small lua daemon, which can be easily extended. Check it out from:

projects/mqtt.1444306288.txt.gz · Last modified: 2015/10/08 14:11 by ihmis-suski