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Freezer alarm with buzzer!
Posted: 24 Oct 2018, 20:24
by Naesstrom
This might be a stupid question but I'm building a freezer alarm with a wemos d1 mini and a buzzer shield, I'm getting the temp from 2 ds18b20's... I've never written a rule before but after some reading I've come up with the following
Code: Select all
on temp#Temperature do
if [temp#Temperature] > -15 // temp warmer then -15ºC
tone,14,1000,700
endif
endon
Havn't tried it yet but will it loop? And how can I add a pause so the sound is beeping and not just a continous tone?
Re: Freezer alarm with buzzer!
Posted: 24 Oct 2018, 20:30
by grovkillen
Rtttl is another command but it will block the loop during the playing. But to stop it after a while you need to use timer and possibly dummy devices to store the state (creating a kind of hysteresis).
Re: Freezer alarm with buzzer!
Posted: 24 Oct 2018, 21:26
by Naesstrom
grovkillen wrote: ↑24 Oct 2018, 20:30
Rtttl is another command but it will block the loop during the playing. But to stop it after a while you need to use timer and possibly dummy devices to store the state (creating a kind of hysteresis).
Yeah I was thinking of making it play the imperial march but since it's going to be at my office I wasn't sure how the other teachers would react
I was looking at the tutorial rules and was thinking about this one
Code: Select all
//start the warning signal when we receive a start_warning event:
On start_warning do
timerSet,1,2
endon
//stop the warning signal when we receive a stop_warning event:
On stop_warning do
timerSet,1,0
endon
//create an actual warning signal, every time timer 1 expires:
On Rules#Timer=1 do
//repeat after 2 seconds
timerSet,1,2
//produce a short 1000hz beep via a piezo element on pin 14
tone,14,1000,700
endon
is that a better way, and then create a rule that sends a
when the temperature is -15 or warmer and a
when the temperature is colder then -15?
Re: Freezer alarm with buzzer!
Posted: 24 Oct 2018, 21:39
by Naesstrom
Actually I tried my first try of the code and it worked super... set it to this:
Code: Select all
on FRYS#Temperature do
if [FRYS#Temperature] > 30 // temp warmer then -15ºC
tone,14,1000,700
endif
endon
And when warming it up over 30 it starts beeping and when it cools down it stops! Just as I wanted it!
hmm... maybe I should do something more fun like a rtttl
Can I add another rule in the same set for the fridge?
Re: Freezer alarm with buzzer!
Posted: 24 Oct 2018, 22:47
by grovkillen
Yeah it shouldn't be a problem.