Hello ramsinsavra, sorry - I made one error: ramsinsavra> Also, does it matter (in terms of performance) if I connect a Vdd to ramsinsavra> the power pin, instead of connecting it to GND? Of cource you have to connect the DS1820 Gnd Pin to the HCxx Vss Pin - and you can connect the DS1820 Vdd Pin to Power - 5 volts. The DS1820 required at least 3.0 volts for Vdd. Sometimes I get confused with Vdd and Vss ... Werner mailto:whsw@whsw...

Hello ramsinsavra, sorry for late reasponse - was a lot of time off-line! ramsinsavra> I got the sensor finally. In your email you had mentioned that there ramsinsavra> are good examples of it. Can you send me a reference? look at maxim-ic.com for DS18B20. There you will find also references to application notes. Interesting are the data sheet itsself and also App148 - 1wire drivers, App162 - Interface the ds1820 to a microprocessor. ramsinsavra> Also, does it matter (in terms of performance) if I connect a Vdd to ramsinsavra> the power pin, instead of connecting it to GND? You have to connect the DS1820 Gnd pin to Vdd - or it will not work. The DS1820 is something like a small microprocesser with a simple 1-Line-serial interface with 0 to 5 volts digital signals on it. You have to connect DS1820 Gnd to Vdd, it's serial line to an "open-collector" output as the D-Port-Pins of the HC11 (you have to set them up as open collectors!) with a pullup to 5 volts of 4k7 and to connect the DS1820 Vss Pin to 5 volts. There are also possibilities to work with only 2 wires to the DS1820 but then things get more complicated. The data sheet and the app notes give a lot of details. Good Luck Werner mailto:whsw@whsw...

Thanks indeed for your advice. --- In 68HC12@68HC..., Kevin Antony <kevin.antony@a...> wrote: > > Try Microchip. I played with a TC1047A and an HC08 processor with success. > Just use the processor's analog to digital converter to measure the output > voltage and calculate the temp based on the datasheet's temp vs. voltage > curve. http://ww1.microchip.com/downloads/en/DeviceDoc/21498c.pdf > > Kevin > -----Original Message----- > From: 68HC12@68HC... [mailto:68HC12@68HC...] On Behalf Of > Ramsin Savra > Sent: Wednesday, November 16, 2005 12:09 PM > To: 68HC12@68HC... > Subject: [68HC12] HCS12 and Sensor > Hello group, > > Can somebody tell me what sensor I should use to capture temperature of a > refrigerator? this is my firs project and I don't know how to select a > sensor. > > Your help will be appreciated greatly. > > Thanks. > > --------------------------------- > Yahoo! FareChase - Search multiple travel sites in one click. > > > Yahoo! Groups Links >

Hello Werner, I got the sensor finally. In your email you had mentioned that there are good examples of it. Can you send me a reference? Also, does it matter (in terms of performance) if I connect a Vdd to the power pin, instead of connecting it to GND? Thanks in advance. --- In 68HC12@68HC..., Werner Wittig <whsw@w...> wrote: > > Hello Ramsin, > > I just repared a refrigerator with a DS18B20 from MAXIM (see maxim- ic.com). It > guarantees +/- 0.3 centigrad and is controlled by a > "1-Wire-Interface". Gives you the temperature digitally. > > I used it with a HC11 at port D (1 pin needed, must be > open-collector). They use a special protocoll but have good examples > how to implement it. > > mailto:whsw@w... >

Thanks a lot for your advice. --- In 68HC12@68HC..., Kevin Antony <kevin.antony@a...> wrote: > > Try Microchip. I played with a TC1047A and an HC08 processor with success. > Just use the processor's analog to digital converter to measure the output > voltage and calculate the temp based on the datasheet's temp vs. voltage > curve. http://ww1.microchip.com/downloads/en/DeviceDoc/21498c.pdf > > Kevin > -----Original Message----- > From: 68HC12@68HC... [mailto:68HC12@68HC...] On Behalf Of > Ramsin Savra > Sent: Wednesday, November 16, 2005 12:09 PM > To: 68HC12@68HC... > Subject: [68HC12] HCS12 and Sensor > Hello group, > > Can somebody tell me what sensor I should use to capture temperature of a > refrigerator? this is my firs project and I don't know how to select a > sensor. > > Your help will be appreciated greatly. > > Thanks. > > --------------------------------- > Yahoo! FareChase - Search multiple travel sites in one click. > > > Yahoo! Groups Links >

1.5 ~ 4.5 degree --- In 68HC12@68HC..., Michal Konieczny <mk@c...> wrote: > > > Can somebody tell me what sensor I should use to capture temperature of a refrigerator? this is my firs project and I don't know how to select a sensor. > > > > Your help will be appreciated greatly. > > What accuracy and resolution do you expect ? > > -- > Michal Konieczny > mk@c... >

Nice! thanks indeed for your suggestion. Also, I have one more question. What about UPS level? I need to check a UPS level connected to the refrigerator and I was told that I should use a special resistance in order to decrease the votage. How do I know which voltage is the appropriate one? I'm totally new to this exciting field. Thanks again. --- In 68HC12@68HC..., Werner Wittig <whsw@w...> wrote: > > Hello Ramsin, > > I just repared a refrigerator with a DS18B20 from MAXIM (see maxim- ic.com). It > guarantees +/- 0.3 centigrad and is controlled by a > "1-Wire-Interface". Gives you the temperature digitally. > > I used it with a HC11 at port D (1 pin needed, must be > open-collector). They use a special protocoll but have good examples > how to implement it. > > mailto:whsw@w... >

Hello Ramsin, I just repared a refrigerator with a DS18B20 from MAXIM (see maxim-ic.com). It guarantees +/- 0.3 centigrad and is controlled by a "1-Wire-Interface". Gives you the temperature digitally. I used it with a HC11 at port D (1 pin needed, must be open-collector). They use a special protocoll but have good examples how to implement it. mailto:whsw@whsw...

> Can somebody tell me what sensor I should use to capture temperature of a refrigerator? this is my firs project and I don't know how to select a sensor. > > Your help will be appreciated greatly. What accuracy and resolution do you expect ? -- Michal Konieczny mk@mk@....

Analog Devices AN7414 10-bit digital temperature sensor. Interfaces to the microprocessor via the I2C port. Ramsin Savra wrote: > > Hello group, > > Can somebody tell me what sensor I should use to capture temperature of a refrigerator? this is my firs project and I don't know how to select a sensor. > > Your help will be appreciated greatly. > > Thanks. > >--------------------------------- > Yahoo! FareChase - Search multiple travel sites in one click. > > >Yahoo! Groups Links > > >--------------------------- >Text inserted by Panda Platinum 2005 Internet Security: > > This message has NOT been classified as spam. If it is unsolicited mail (spam), click on the following link to reclassify it: http://127.0.0.1:6083/Panda?ID=pav_7051&SPAM=true >--------------------------- > > -- Bob Harris Can MOTCH Katmai Henry David Thoreau, UDX, Bda UD (1992-2005) Longmeadow Bradford Torrey, CD Bath, NH