Return to indexReturn to indexTo make some electronic components to use which I bought years ago, I decided to have some temperature sensors around the house and make them visible on the internet. For this purpose I still had a 80C552 board that I never had used yet. The 80C552 is a 80C32 compatible chip with some additions, like 8 channel ADC (analog to digital converter). I am using as a temperature sensor the LM335. This sensor gives per decrease Kelvin a voltage of 10 mV and is very inexpensive. The ADC of the 80C552 has a resolution of 1024 steps. So I am using a temperature range of 102.4 degrease and that makes an accuracy of 0.1 decrease.
Because the 80C552 had lots more I/O ports, I thought I would try to see if it could track my electricity use. My electricity meter has a build in LED that signals when 1 Wh is used up. So 1000 flashes make 1 kWh. I used a phototransistor to pick up the flashes from the meter. The phototransistor didn't seems to be sensitive enough so I used a darlington configuration to amplify the pulse. After that it worked fine.
The pages with the temperatures and electricity use are CGI generated. Click on the links below to see them
Temperature sensors (not working at the moment!)Below is the link to the source of the 80C552. It is written in µC51 ansi-C.
80C552 sourceBelow some pictures of the project
Return to index
| |||||
| |||||
