Reading a GA and displaying the value in decimal via PHP

[Warichet]

Hi,

I'm trying to read and display a GA (temperature) with PHP.
I've read the procedure on the KNX site, but I wonder if someone has already done it with PHP or similar ? (from ETS -> décimal)

Thank you.

[Warichet]

Maybe this, testing ...

[Bodo]

Hoi
Have a look at PDF:
http://www.knx.org/fileadmin/downloa....5.00%20AS.zip
Page 31 I think

3.10 Datapoint Types “2-Octet Float Value”
Format: 2 octets: F16
octet nr: 2 MSB 1 LSB
field names: FloatValue
encoding: MEEEEMMM MMMMMMMMM
Encoding:
FloatValue = (0,01*M)*2(E)
E = [0 … 15]
M = [-2 048 … 2 047], two’s complement notation
For all Datapoint Types 9.xxx, the encoded value 7FFFh shall always be used to denote invalid
data.
Range: [-671 088,64 … 670 760,96]
PDT: PDT_KNX_FLOAT

[callidomus]

Hi,

see the eibd examples threre is a simple php client.

hth

Marcus

[Warichet]

Hi,

see the eibd examples threre is a simple php client.

I don't feel at home within eibd, I would appreciate a pointer to the file

Thank you

[callidomus]

Hi,

I dont know the path. Download the source code and look for a php file. On Linux you could use: find . | grep php

So Long

Marcus

[Warichet]

Download the source code and look for a php file.

That's what I did before posting.
No luck

Thanks anyway

[Warichet]

Hi,

I'm unable to make anything consistent with the conversion.
Here is an extract of the code

$value = GroupRead("127.0.0.1","0/6/38");
....
$eis5 = hexdec($value);
$wert = ($eis5 & 0x07ff);
if (($eis5 & 0x08000) != 0)
 {
 $wert = $wert | 0xfffff800;
 $wert = $wert *-1;
 }
$wert = $wert << (($eis5 & 0x07800) >> 11);
if (($eis5 & 0x08000) != 0)
 {
 $wert = $wert * -1;
 }
$val = $wert/100;
......
$string = "Temp: " . $val . "°C"; 

Maybe a sharp eye will see the problem ?

[Warichet]

There is something wrong with the GroupRead
When I force the input to a known value, the conversion works fine, i.e: 1902 = 20,64°

$value = GroupRead("127.0.0.1","0/6/38");
$value = 1902;
$eis5 = hexdec($value);
$wert = ($eis5 & 0x07ff);
if (($eis5 & 0x08000) != 0)
 {
 $wert = $wert | 0xfffff800;
 $wert = $wert *-1;
 }
$wert = $wert << (($eis5 & 0x07800) >> 11);
if (($eis5 & 0x08000) != 0)
 {
 $wert = $wert * -1;
 }
$val = $wert/100;
......
$string = "Temp: " . $val . "°C"; 

[Warichet]

This is beyhond my understanding.
The command GroupRead is not to be suspected as it works in other applications in the same environment.

The conversion is not to be suspected as it works with a fixed value.

But the 2 together, no go.

Anyone has an idea, please ?

[callidomus]

I'm not sure that I could help you, but I give it a try. What is the return value of the Groupwrite command?
And you do have an running eibd, which listens on 127.0.0.1.

Marcus

[Warichet]

I give it a try.

Much appreciated, thank you aforehand

What is the return value of the Groupwrite command?

0.23 which is totally inconsistent
The actual temp as shown in the Visu is 21.8

And you do have an running eibd, which listens on 127.0.0.1.

Yes, I understand that's the standard way of doing.
eibd is running on a NAS QNAP with PHP5.
I've another application to display KNX data on a Cisco phone, also using PHP, and it is working fine, using the same GroupRead.

Thanks

[callidomus]

I think I see your Problem. You are using the wrong decoding function. Floating Point values are a little ugly to decode, but there should be a function in the client.

I'm on a Road Trip and have no access to my dev computer. => you have to Look for the right function by yourself.

So long

Marcus

[Warichet]

You are using the wrong decoding function.

Ah ?!? some light in my tunnel

there should be a function in the client

I've seen the function f2_decode($val), it doesn't work either, maybe it was the wrong one.

you have to Look for the right function by yourself.

OK, I'll have a closer look.

Thank you for the hint.

PS: I was convinced it was the right function, because when I type a value, as seen in ETS, I get the right output.

[NilsS]

Hi Ray,

maybe this can help you get eis5 (DPT9) decoding done.
SourceForge.net Repository - [openautomation] Contents of /PyWireGate/trunk/knx_connector/DPT_Types.py

Its in python but that shouldn't be to hard to port to php.

There is also a DPT Type guessing function.