Ok John, sorry If I wasn't too specific. Temperature range: 5 -15 C. Resolution: about 0,2 C. at least 6 samples /day (but much more samples will be better!). If I can write the data also into the program memory ,as you say, is a nice stuff!! I have to build some of these "ball loggers" (every unit sealed into a plastic ball for underwater use) for water temp. analysis in an underground river. thanks for the reply Marco ----- Original Message ----- From: "Jon Baker" To: Sent: 7 marzo, 2002 15.32 Subject: Re: [PIC]: mini 16F876 datatogger > I suppose it really depends how often you need to sample the temperature, > the temperature range you are looking at and the acuracy you require. For > instance if you expect the temperatures to be between 20 and 27 degrees C, > and you need results to the nearest degree, you would only need 3 bits per > result and could therefore fit 682 results in the eeprom or just over 11 > samples per day for 2 months. I believe you can write to program memory > with the 876. > > Some more specific info would help greatly. > > -- > Jon Baker > > ----- Original Message ----- > From: "marco genovesi" > > > > A newbie question. > > I would like to build a very small, cheap and easy to-assembly > temperature > > datalogger (about 1" x 2" sized) to use for a strange problem. Due to the > > small size, I'm thiking to use only a single PIC chip (no external > EEPROM). > > Probably a smaller size will be possible using an 8pin PIC and a serial > > eeprom as 24LCxx, but I have some 16F876 and I want use them. These are my > > specs: > > > > - Size 1" x 2" (about) > > - 32Khz clock > > - Temp.measure with a thermistor. > > - one 3V lithium cell > > - >= 2 months operativity > > - >= 150 bytes data storage > > -- > http://www.piclist.com hint: To leave the PICList > mailto:piclist-unsubscribe-request@mitvma.mit.edu > > -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu