BS2 and the DS18B20+ TO-92 pkg

Yoshti

Hi everyone,
I'm brand new into this world of Electronic.
I bought the ACTIVITY kit and went through it all. Just great. I did not catch all of it. But I will learn one day

I'm trying to get the ONE WIRE or standard connection for the DS18B20+ using my kit.
And searching through any available forum, they all used the BS2P and other.

The problem I get is the OWIN and OWOUT which BS2 does not have.
How can I get the same pin to send and receive data to talk to DS18 ?

Some example I found was using "In the middle" ONEWIRE PIC which I don't have. I just have the kit to work with.
Reading the nuts and volts too, it is still not obvious for me. I'm lost at best ... very noob as you can see.

Can this be done with the BS2 ? (with no other chip).

Cheers

Mike Green

The BS2 can't do 1-wire protocol. It doesn't have the built-in statements and it's not fast enough to "bit-bang" it (use the LOW / HIGH / INPUT statements to do the same thing). You have to use the BS2p/pe/px models. There are other temperature sensors and real time clocks that use the SPI protocol which the BS2 can do using the SHIFTIN and SHIFTOUT statements. There are subroutines described in one of the Nuts and Volts Columns that will handle I2C protocol which is used for all sorts of parts.

Yoshti

Hi Mike,
Thank you for the HEAD-BANGING cushion ..
Ok so, my little three legged friends now just started to collect dust-- or is there a way to add a chip to get it to work ?
I suspect you will send me to the store and will also suggest a model which temp sensor would be best for me. 80)

Cheers

Thank you again for the quick response... I was getting a headache here...

Yoshti

Hi again,
I guess , by searching on Parallax, the DS1620 would do a great job.
And technically, I could use 5 ea. on one BS2 board. Each Sensor requires 3 pins.

Any problems ahead if I use 5ea DS1620 temp sensors on my activity board?

Cheers

Tracy Allen

Five DS1620 sensors would require only 7 pins, not 15, on your BS2. The data and clock lines can be shared, and only the chip select lines need to be separate.

Another temperature sensor that just uses one pin is the TMP-04 (Analog devices). The Stamp interface uses the PULSIN command and temperature is encoded in the ratio of time high to time low. Unlike OneWire, though, you can only have one sensor connected to each pin, and not an addressable string of several.

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Tracy Allen
www.emesystems.com

Mike Green

There are a variety of devices that will allow you to attach 1-wire devices to a microprocessor (like the BS2) that only speaks SPI or serial. The DS2480B interfaces between a serial port and 1-wire. I haven't looked at the part in detail, but the serial interface would work with the Stamps' SERIN / SEROUT statements. I'm not sure of the timing details and whether the Stamp can process the serial data fast enough.

Yoshti

Thanks guys...

I'll be looking at upgrading. Looking at the BS2P24 module and using the carrier board BS2.
I think at my level, I'll be able to use it for a long time!.

If I intend to build a Altimeter, compass , accelerometer and temp sensors...and LCD Displays

Is the BS2P24 have enough horse power to run them all?

The speed for each component is not that crucial: I don't need updating my compass every 1/10 of a sec, or the Altimeter... As long as it is half decent time.
I've successfully done the COMPASS works great ! all info taken from the forum ... great info in here... Just awesome to see the expertise level in here !!! Hats off!

Mike Green

The BS2p24 should work fine. You didn't say what kind of sensors you'd be using, but the P-series has support for 1-wire and I2C as well as having additional memory and speed.