Simple thermometer

6 Jan 2017

I would like to show you a simple thermometer with single seven segment LED display HP 5082-7356, DS18B20 sensor and Digispark module. DS18B20 sensor is able to measure temperatures in range form -55 to 125 °C. Digispark module communicates with DS18B20 sensor by 1-Wire interface and reads temperature every 10 seconds. Value of temperature (stored as integer) is displayed on HP display.

Schematic:

Video:

Source code:

sevensegtherm

Top Comments

mcb1 over 8 years ago +3

Nice post. jw0752 see if you can expand it to 2 digits not enough pins on a Digispark. BUT if you use I2C you can drive an LCD. This one sensed the temperature, displayed it and sent a code via 433Mhz…
jc2048 over 8 years ago +1

I like it. Minimal and a bit retro in looks. That HP 7-seg display with a decoder must go back a bit.
kk99 over 8 years ago in reply to mcb1 +1

Yes, I know that bootlader takes some time at startup. I think that for drive more displays e.g. 4 digits with dot points, we could use I/O expander with I2C bus e.g. PCF8574.

Parents

mcb1 over 8 years ago

Nice post.

jw0752
see if you can expand it to 2 digits
not enough pins on a Digispark.
BUT if you use I2C you can drive an LCD.
This one sensed the temperature, displayed it and sent a code via 433Mhz to a RF power Power socket to switch on the fan/heater.

Mark
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balearicdynamics over 8 years ago in reply to mcb1

Not sufficient too for a shift register ?

Enrico
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balearicdynamics over 8 years ago in reply to mcb1

Not sufficient too for a shift register ?

Enrico
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mcb1 over 8 years ago in reply to balearicdynamics

My mistake ...
In theory you could use the 6th line.

But all these options sort of negates kk99 idea of a simple limited component temperature display.

BTW did you know there is a bootloader that removes the 5 sec delay on power on.

Mark
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kk99 over 8 years ago in reply to mcb1

Yes, I know that bootlader takes some time at startup.

I think that for drive more displays e.g. 4 digits with dot points, we could use I/O expander with I2C bus e.g. PCF8574.
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