A first idea for a super simple RS232 temperature probe with the temp PIC

my PIC temp sensor.

Yes. As always, you are the pathetic joke.

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Reply to
Michael A. Terrell
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Bullshit It is an amateurish piece of low grade crap. It can not be certified for commercial use, so it is garbage.

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Reply to
Michael A. Terrell
[...]

No need for PIC:

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VLV

Reply to
Vladimir Vassilevsky

Does the DS18s20 output in ASCII ??

don

Reply to
don

Do you?

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Reply to
Michael A. Terrell

LOL, Yes, with a PIC.

don

Reply to
don

On a sunny day (Sun, 16 Aug 2009 17:30:56 -0500) it happened Vladimir Vassilevsky wrote in :

That is not RS232 and does not interface with the computer serial port.

Reply to
Jan Panteltje

No, the PIC puts out ASCII.

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Reply to
Michael A. Terrell

No, the program I wrote puts out ASCII.

The DS18S20 requires some master I2C device to transfer its internal data and convert that data to ASCII.

don

Reply to
don

Eh? Eh?

If you have enough of brains to understand the difference between I2C and 1-wire, it shouldn't be a problem for you to connect DS18S20 to COM port and convert it to ASC-II.

Vladimir Vassilevsky DSP and Mixed Signal Design Consultant

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Reply to
Vladimir Vassilevsky

So very true !!

And those brains were programmed into a PIC.

Is there a problem with using a PIC for this project, or is everyone just in a pissy mood.

Weather its a PIC@4Mhz or a P4@4Ghz, code still needs to be written.

And the PIC or P4 will not generate that code by itself.

I thought Panteltjes project was clever.

Or is this thread just PIC bashing ??

don

( Sometimes I'm slow, and the rest of the time I don't catch on at all )

Reply to
don

"Those brains" are not needed at all. A DS18S20 can be connected directly to a serial port, if you're willing to add some passives, just like the OP did. Better, you can add *multiple* DS18S20's without needing more passives, since they share the same 1wire signal. You can wire them up and daisy chain them with a single twisted pair.

You need software on the PC, of course, but you'd need that no matter what your hardware looks like. The PC software does the ASCII conversion.

Reply to
DJ Delorie

On a sunny day (18 Aug 2009 12:21:54 -0400) it happened DJ Delorie wrote in :

Well, it is 5 $ in single quantities at digikey. Also needed is the time to write the special software, for say MS Windows and of course Linux, and perhaps Apples.

My PIC costs about 1 $, and works with all three computer OSes with any terminal program. But you need a PIC programmer, and an assembler. But writing special soft for all those OSes is much more expensive :-)

Actually I think their system sucks even more, say you need a 10 point multidrop. _Unless_ those chippies come each with a piece of paper with a 64 bit code on it. you need to have a software setup to detect its code, and then give each a human readable number and make a database with code versus that number. Else what is what? Also it needs an extra MOSFET, for any number of them, not just passives.

A great application for my temp_PIC, is to use the mode where it flashes a LED when temperature is within a specific range, could be baby milk, or tea, or coffee, could save somebody like Mc Donuts (spelling?) millions.....

With a 3V lithium it could be build into each coffee cup, hehe, drinkable only when green LED flashes, hurry hurry! This I have to try for sure.

So, my PIC can be used stand alone too, and needs no 64 bit fiddling. All application ideas mentioned here for temp_pic I hereby declare public domain. Make them in the millions :-)

Reply to
Jan Panteltje

I didn't say it was cheaper, I just said you don't need to add a PIC to it.

And you need to write that software, and include a programming jack on your device.

Yes? So? How do to do a 10-point multidrop with your PIC?

As for the software, it's part of the standard way of doing 1wire. You plug in a device, it says "Hey! Something new..." and you tell it what it is. Then plug in the next device... etc. My furnace control system has... [hmmm, counts] seventeen 1wire devices in it. Getting the serial numbers is not a big deal.

No, just a diode. With a PIC or MCU driving it, you need no passives

- just connect the 1wire device to a GPIO and do it all in software.

Easier to do with thermochromic inks.

Reply to
DJ Delorie

On a sunny day (18 Aug 2009 14:23:51 -0400) it happened DJ Delorie wrote in :

No but then what is the point? The PIC is more versatile and cheaper.

No way, the program is written and in the public domain, available from here:

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And you program the PIC _before _ you put it into anything. There is no in-circuit programming required.

It is actually very easy. You must, as you have been around long enough, know about the old Intel 8051 ninth data bit. So now we add an RS232 input, and the master (PC) sends an address (bit 9 low), and the slave with that address is the one that replies by pulling the RS232 TX line low and sending its reply. But you do not even need the ninth bit, as one can use the same soft UART and use bit 7 as address bit, sending a special character will then address up to 127 devices. With a normal terminal program.

The thing that some people fail to see is the power of programmability of the PIC solution. Although I used defines for many obvious functions in that asm source on my site, clearly you can do anything you want. Also I have not even used the interrupt or main routines, just the watchdog resets.

Not enough pull up, that thing needs 1.5 mA and shorts with a 100 Ohm MOSFET, A clumsy system.

Yes, sure, now you need a MCU all of the sudden, hey but my PIC *IS* one. hehe

And you can walk on your hands from LA to NY too I suppose.

Reply to
Jan Panteltje

DJ is right. This looks very simple and much cheaper:

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Reply to
Nico Coesel

On a sunny day (Tue, 18 Aug 2009 19:21:24 GMT) it happened snipped-for-privacy@puntnl.niks (Nico Coesel) wrote in :

There is one temp sensor, and the links says: ; PuceBaboon is not currently accepting any new orders for products, services or components. ; ; Support for existing customers is available via snipped-for-privacy@PuceBaboon.com ; ; Software is still available for free download.

And nothing is simpler, even even less cheaper. Did you even read the links?

LOC

Reply to
Jan Panteltje

The point is that I was trying to help people understand how the technology works? I don't understand why you're sounding so hostile to me.

It has its strengths and weaknesses, just like 1wire parts. Some of the 1wire parts I use have built-in thermocouple sensors. Some have multiple ADCs *and* temperature. Some others on the market have EEPROM. None have MCUs in them. Different parts are different, so let's learn what they all can do so we can all choose well.

As are 1wire programs. It's still all software that needs to (or needed to) be written.

DIP? Or other sizes? I usually use tiny SMD parts; they're easier to program after they're installed.

I haven't failed to see that. But the PIC isn't the end-all-be-all of electronic devices, either.

Seems to work for lots of people, which is all you claim for your device.

Sigh. Why are you fighting me on this? I'm just trying to tell people a little more about 1wire parts, and clear up some misconceptions, and you suddenly think I'm the anti-pic or something. I've used PICs before. I'm a big fan of tiny processors (my furnace has six CPUs in it, five tiny ones and an embedded linux chip).

Um, no? Where did you get this idea? What does it have to do with thermochromic inks?

Reply to
DJ Delorie

On a sunny day (18 Aug 2009 18:32:28 -0400) it happened DJ Delorie wrote in :

Well I try to avoid arguing for the sake of arguing. This already went that way. Sure 1 wire, 100 wire, wireless, whatever have you, solutions can _also_ work. Thermochromic inks will not really warn you as much as a flashing LED. Neither can it keep a lid closed (to avoid pouring out too hot stuff), or be used for zillion other (control) solutions and or applications... However you slice it, sure do your thing. This was my contribution, I already have mentioned some nice things it can be used for, you can make it as simple or complicated as you want. You can do one wire with the PIC too, I can even mimic that other chip with it and the master (PC) would not know the difference. I have programmed a PIC in the past to behave like a well known i2c chip ... (in software not a PIC with i2c interface). There is only _one_ point where this PIC solution as temperature measuring device is 'less' then that other chip: accuracy. So in applications where you need to be very accurate you use something else then that PIC, or a PIC with some external sensor. In all other applications the PIC is more versatile, even the smallest one. Assuming you can program one.

That is really all there is to it. I was on the next project already...

Sure there are PIC haters here... It is easy to get frustrated with PIC, I had a hard time here myself, due to some Microchip example code not working. When you give up, then you will also be defeated by the next micro.... And there are those who do it in BASIC in a small PIC.... For me I want to be as close to the hardware as possible with these little computers. So asm. A bit of asm and clever use of the PIC hardware resources can replace tons of hardware. But you already know that,

Reply to
Jan Panteltje

or components.

No need to. Build the interface, connect the chip DJ pointed to and download the software.

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Reply to
Nico Coesel

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