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Hi,

I need a definitive answer to my one wire problem please.

Regarding my previous posts on the subject, I'm still having no luck after using various methods.

Will someone please tell me in what format the 'data' is returned after a temp. conversion. i.e. 9 bytes, bytes 0 & 1? etc....

 

The sensor is working regarding the s/ware and h/ware sides of it, but, I cannot work out how to use the data, (which returns as -1 and doesn't vary at all with temperature).

With the lcd header file it can be opened and you can work out what is happening not so with the one wire header. Does it actually work? Has anyone proved it?

 

Looking forward to an interesting answer.

Regards,

Daz. :P

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These devices (as per datasheet) can return all 9 scratchpad reads, of those only two are needed for minimal

temperature reading. ( Two give you the basic plus, minus, leading integer values and either .0 or .5 )

 

Be aware if your american and i am remembering correctly, the values returned are in C not F.

 

For your reference:

-Page 3 gives reference return values.

-Page 6 gives you the description of all 9 scratchpad returns.

http://pdfserv.maxim-ic.com/en/ds/DS1820-DS1820S.pdf

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These devices (as per datasheet) can return all 9 scratchpad reads, of those only two are needed for minimal

temperature reading. ( Two give you the basic plus, minus, leading integer values and either .0 or .5 )

 

Be aware if your american and i am remembering correctly, the values returned are in C not F.

 

For your reference:

-Page 3 gives reference return values.

-Page 6 gives you the description of all 9 scratchpad returns.

http://pdfserv.maxim-ic.com/en/ds/DS1820-DS1820S.pdf

 

 

Thanks for the reply, but, perhaps I wasn't clear enough in my post. I realise (from the dallas data sheet) that 9 bytes are returned, however, the answer I need is what exactly does the return char 'data' in the 'oo_get_data' function contain as far as the sourceboost ide is concerned, bytes 0 & 1, which contain the temp. data or the full 9 bytes?

Regards,

Daz.

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oo_get_data() does exactly what one would expect it to do. It is a generic handler to take data off the

onewire. This means it will return only the first byte if you just drop it in plain.

For the dallas sensor you would have tto call it 9 times for all the bytes.

 

i did not think any aspect was really that obscure ...

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oo_get_data() does exactly what one would expect it to do. It is a generic handler to take data off the

onewire. This means it will return only the first byte if you just drop it in plain.

For the dallas sensor you would have tto call it 9 times for all the bytes.

 

i did not think any aspect was really that obscure ...

 

Thanks emte,

At last it makes more sense, I will now re-evaluate and hopefully get the desired result.

Regards,

Daz. ;)

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