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bigmik

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Joined: 20/06/2011
Location: Australia
Posts: 2914

Posted: 10:33pm 28 Dec 2011

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Ray B said
FYI the DS18B20's are some 3 for A$5.20 total inc postage from China alongside an original $10 purchase from Aussie supplier some time back.

Hi Ray,

Where can I get them from China? I was looking locally and they were a bit steep here.

Regards,

Mick

EDIT !!!

Don't worry mate, I used my brain and found them on eBay... I was a bit sus about the gold painted ones as they may have been fake so I paid $12.88 for 10 of them.

MickEdited by bigmik 2011-12-30

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

seco61
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Joined: 15/06/2011
Location: Australia
Posts: 205

Posted: 11:37pm 28 Dec 2011

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Hi Ray.

Based on the results you have posted, it would appear that the devices are all operating within their specifications:

"Accuracy over the range of -10�C to +85�C: �0.5�C"

Ray B said I've always wanted to confirm the accuracy / repeatability of readings of DS18B20.

Following is a test result using the code above and 4 x DS18B20 side by side in a section of protoboard in free airspace.

FYI the DS18B20's are some 3 for A$5.20 total inc postage from China alongside an original $10 purchase from Aussie supplier some time back.

Regards

Gerard (vk3cg/vk3grs)

Keith @

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Joined: 19/06/2011
Location: Australia
Posts: 167

Posted: 11:37pm 28 Dec 2011

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Mick

I got mine from Sure Electronics (.net) or they're on ebay... haven't had any problems with them. Search for DS18B20.

Beware ... the tank probes don't have sealing washers and you have to cut the connector off the end of the lead to get the nut off

Keith

The more we know, the more we know we don't know !

Ray B
Senior Member

Joined: 16/02/2007
Location: Australia
Posts: 219

Posted: 02:04am 29 Dec 2011

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Mick yes the Gold Painted DS18B20 look a bit sus but will be good to see how they run.

Choice of probes on ebay is interesting especially as Keith commented, the tanked probes, which sound like the way to go for duct temperature (air conditioning) monitoring or liquids (home brew).

Gerard can you confirm that "1030 io_pin = 18 ' I/O pin to use" will only work for i/o 11 - 20 BUT NOT i/o 1-10. This is how it seems to me from playing around so far.
Assume this because i/o 1 - 10 only work up to 3.3 volts.

Once again Gerald thanks for this enhancement.

Now need to see how MM can say be running a base program, let's call it MAIN: then make sub routine or function calls to the 1WIRE code to extract values to use in MAIN:

Cheers

RayB from Perth WA

bigmik

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Joined: 20/06/2011
Location: Australia
Posts: 2914

Posted: 03:17am 29 Dec 2011

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Ray B said Mick yes the Gold Painted DS18B20 look a bit sus but will be good to see how they run.

Yes, I may not have been 100% clear.. I could have got 10 of the gold painted ones for $9.xx but I bought the non-painted ones.. I am not sure why the others are gold but they do not look legit..

Strangely the ones I bought are called `refurbs' I dont know how you would refurb a to-92 device... maybe they mean `pulls' from salvaged equipment.

Time will tell

Rgards,

Mick

Mick's uMite Stuff can be found >>> HERE (Kindly hosted by Dontronics) <<<

seco61
Senior Member

Joined: 15/06/2011
Location: Australia
Posts: 205

Posted: 09:11am 29 Dec 2011

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Hi Ray.

The code for the Maximite is set to only allow pins 11 - 20. I did this as Geoff has only allowed pins 11 - 20 to be used as digital open collector (open drain really) outputs and did not want to confuse people as the one wire devices operate in open collector mode.

There is no technical reason why it can not work on all 20 pins - on the Duinomite we have set up the code to allow open collector outputs on all pins. You just have to be aware of which pins are 5V tolerant and which are not. You could request Geoff to change the current Maximite code. If you would like a version of the Maximite firmware that allows all 20 pins (for both open collector and/or one wire) I could easily change the code.

The one wire devices will run at 3.3V - and that is what I am using to test with here.

Ray B said Mick yes the Gold Painted DS18B20 look a bit sus but will be good to see how they run.

Choice of probes on ebay is interesting especially as Keith commented, the tanked probes, which sound like the way to go for duct temperature (air conditioning) monitoring or liquids (home brew).

Gerard can you confirm that "1030 io_pin = 18 ' I/O pin to use" will only work for i/o 11 - 20 BUT NOT i/o 1-10. This is how it seems to me from playing around so far.
Assume this because i/o 1 - 10 only work up to 3.3 volts.

Once again Gerald thanks for this enhancement.

Now need to see how MM can say be running a base program, let's call it MAIN: then make sub routine or function calls to the 1WIRE code to extract values to use in MAIN:

Cheers

Regards

Gerard (vk3cg/vk3grs)

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 08:34pm 30 Dec 2011

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Hi Gerard

seco61 said If you would like a version of the Maximite firmware that allows all 20 pins (for both open collector and/or one wire) I could easily change the code.

I think this would be great (Will suit my addon PCB :) )

Regards

John

seco61
Senior Member

Joined: 15/06/2011
Location: Australia
Posts: 205

Posted: 11:04pm 30 Dec 2011

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Hi John.

I have sent you an updated firmware for the Maximite that allows open collector outputs and one wire support on all pins.

You may post it to the forum.

jman said Hi Gerard

seco61 said If you would like a version of the Maximite firmware that allows all 20 pins (for both open collector and/or one wire) I could easily change the code.

I think this would be great (Will suit my addon PCB :) )

Regards

John

Regards

Gerard (vk3cg/vk3grs)

Ray B
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Joined: 16/02/2007
Location: Australia
Posts: 219

Posted: 01:40am 31 Dec 2011

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Gerard any reason why you can't publish the "allow 20 pin" solution to all that you offer to John.?
Like others I'm sure, I'm trying to maintain hardware compatability with certain allocation of functions to output pins like LCD connections and the dual serial comms ports etc to maintain code standardisation so if we can start to better use i/o 1 - 10 that would be an obvious benifet to us MM users.
Cheers & HNY to all

RayB from Perth WA

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 01:41am 31 Dec 2011

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Hi
Gerard has kindly updated the 1-Wire code to allow the 1-Wire protocol
to use any of the 20 IO pins

Code attached
2011-12-31_114059_Maximite-1w-v3.zip

Regards

John

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 01:43am 31 Dec 2011

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Hi Ray

Seems we were typing at the same time :)

John

Keith @

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Joined: 19/06/2011
Location: Australia
Posts: 167

Posted: 06:37am 31 Dec 2011

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Keith @ said Mick

I got mine from Sure Electronics (.net) or they're on ebay... haven't had any problems with them. Search for DS18B20.

Beware ... the tank probes don't have sealing washers and you have to cut the connector off the end of the lead to get the nut off

Keith

Hi Guys

The time came to cut the connector off the end of the temperature probe lead and I took a closer look ....

I grabbed a sturdy needle (I used a hat pin!!!) and I pushed it between the end of the metal tab on the conductor and the plastic housing and pulled on the wire and out it came easy as that ... off came the nut ... now I can go get some food grade washers ...

Keith

The more we know, the more we know we don't know !

CircuitGizmos

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Joined: 08/09/2011
Location: United States
Posts: 1425

Posted: 03:59pm 31 Dec 2011

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Keith @ said now I can go get some food grade washers ...

It's OK to eat nuts, but not washers. :-P

Micromites and Maximites! - Beginning Maximite

donmck

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Joined: 09/06/2011
Location: Australia
Posts: 1313

Posted: 07:33pm 31 Dec 2011

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CircuitGizmos said

Keith @ said now I can go get some food grade washers ...

It's OK to eat nuts, but not washers. :-P

It's hard to find a food grade washer this time of the year.

12 years today since the Y2K bug. Can I stand down now, and stop worrying?

Happy new year. ../// ///// .//// ..///

Cheers Don...Edited by donmck 2012-01-02

https://www.dontronics.com

centrex

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Joined: 13/11/2011
Location: Australia
Posts: 320

Posted: 11:50pm 31 Dec 2011

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Hi all

[Gerard has kindly updated the 1-Wire code to allow the 1-Wire protocol
to use any of the 20 IO pins

Code attached
2011-12-31_114059_Maximite-1w-v3.zip]

Is this a software upgrade for the Maximite that I can just load and still have all the normal functions with the addition of the 1 wire devices.
I am at a bit of a loss with all that is happening to the Maximite.
regards
Cliff

Cliff

jman

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Joined: 12/06/2011
Location: New Zealand
Posts: 711

Posted: 12:16am 01 Jan 2012

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centrex said Hi all
Is this a software upgrade for the Maximite that I can just load and still have all the normal functions with the addition of the 1 wire devices.
I am at a bit of a loss with all that is happening to the Maximite.
regards
Cliff

Hi Cliff

Correct all the normal functions are still there

John

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