KNX/EIB Temerature conversion

[Warichet]

Hello,

I'm looking for the temperature conversion algorythme, from 2 bytes hex to decimal.

I know it has been discussed several times, I checked the Wiki, but can't find it back (lack of the right keywords).

Thanks for any pointer (sorry for the trouble )

[Uwe!]

hilft Dir das weiter???

Hatte ich mal für mcih geamcht, glaube die letzte Version wahr voll funktionsfähig, aber ohne Gewähr

[Warichet]

Hi Uwe,

hilft Dir das weiter???

Looks good, but doesn't work for me.
I guess I've to input the data in B4 ? maybe my Exell is too old ?

I would be happy if you have the procedure "written on paper" so I can do it myself.

Thank you for the quick reply

[Warichet]

Oups, forgot to attach the picture
I think it has to do with the punctuation which is not the same between your version and mine

[Uwe!]

I guess I've to input the data in B4 ? maybe my Exell is too old ?

Yes, B4.

And probably your Version isn't to old (2003 is fine), but you have to activate the Add-In "Analysis ToolPak", cause I use the function "HEX2BIN" from this Add-In.

the logic is quite simple.

convert hex to binary (0af0 = 00001010 11110000)

Bit 1 (from left!) is sign (0)
Bit 2-5 is Exponent (0001)
Bit 6-16 is Mantisse (01011110000)

convert Exponent to decimal (1)
convert Mantisse to decimal (752)
if sign is "1" substract 2048 from Mantisse (still 752)

Temperature = 0,01 x Mantisse x 2^Exponent
= 0,01 x 752 x 2^1
= 0,01 x 752 x 2
= 15,04

[Warichet]

you have to activate the Add-In "Analysis ToolPak

OK, thanks

I tried oaf0=15,04 OK fine
I tried 463c
manually = 4085,76
with the tool = -1157,12

[Uwe!]

see above:

Geändert von Uwe! (Heute um 14:08 Uhr) Grund: Datei getauscht, war noch ein Fehler bei negativen Zahlen drin

please donload again, one formula was wrong!

[Uwe!]

If you're looking for some possiblity to check:

Tapko: Tools

[Warichet]

please download again

You are the king

If you're looking for some possiblity to check:
Tapko: Tools

Nice, thanks for this usefull pointer

[Uwe!]

not at all!