First public release: tempsensor-1.0 - 27-02-2002
Tempsensor is a simple FreeBSD program to interface with a Sensirion SHT11
The sensor must be hooked up to the parallel port.
The program simply spits out two values: Temperature and Humidity.
Connect the SHT11 sensor to the parallel port as shown in this table :
The data output pin of the parallel port should poll the data-line low, but not push it high. Otherwise the SHT11 would not be able to pull the data-line low.
So the anode of the diode is connected to pin 2 of the SHT11 and the cathode is connected to the parallel port. Any diode (e.g. a 1N4148) will do
I used the power of 3 data-bit's of the parallel port to power the SHT11.
You could also choose to power it with an external 5V power supply.
The entire circuit diagriam I used to connect the sensor looks like this :
Email me with questions/comments : Daan <Daan @ pa4dan . nl>