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FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 00:41
von marian
Hi,

what is the duty cycle (sende begrenzung) of FHZ 1300 PC?
How many commands can it send per hour?

Regards,
Marian

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 14:35
von fsommer1968
Hallo,

ich versuche mich an einer Antwort, falls jemand anderer Meinung ist, bitte kundtun (Die benutzten Rechenwerte habe ich bei http://fhz4linux.info/tiki-index.php?page=FS20+Protocol abgekupfert):


Länge eines Datentelegramms: 40 oder 48 Bit plus 12 "0"-Bit, ein "1" Bit zur Synchronisation, ein "0"-Bit für EOT ==> 48 Bit annehmen für Berechnung plus 14,45 Millisekunden für Synchronisation
Dauer eines "1"-Bit: zwischen 1000 und 1450 Mikrosekunden (ein "0"-Bit ist immer kürzer) >> 1450 Mikrosekunden annehmen für Berechnung

Daraus folgt die "Berechnung":
48 Bit * 1450 Millisekunden + 14,45 MIllisekunden sync == 84,05 Millisekunden pro Datentelegramm
Jeder Befehl wird drei mal mit jeweils 10 ms Pause gesendet == 84,05 ms * 3 + 30ms == 282,15 ms pro Befehl
Anzahl Befehle auf dem Kanal == 1/282,15e-3 == 3.544 pro Sekunde

Anzahl der Befehle pro Stunde== 3,544 * 3600 == 12759

Bei Einhaltung der Sendebegrenzung von 1 Prozent == 127 Befehle pro Sender

Wenn man nur die Anzahl der Datentelegramme berücksichtigt ohne Wiederholung kommt man auf 428 Datentelegramme pro Stunde pro Sender

And the result in english:

It is allowed to send 428 datagrams which is similar to 127 commands per device per hour with respect to the limitation of one per cent duty cycle.

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 16:56
von marian
Thanks for the answer!

So if I understand german text correctly, I can send little bit more than 127 commands per hour (127 would be if the commands consists of "1" bits only).
Actually it corresponds to min 24sec sending interval many sensor senders have.

It's ok for everything but central unit, where it is quite limiting.
I guess it can't be done but just in case - can the limit be increased for FHZ1300PC via some command?

(Answer in german is ok, I understand it enough, I just can't write in German yet).

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 17:20
von fsommer1968
The FHZ central unit is just a sender like any other FS or FHT modules. With homeputer studio the command "zeitkontoreset" is possible. This command allows you to send more than 127 commands per hour. But to ensure that over a longer period the 1% rule is not exceeded, this command can be executed only once per 90 minutes.

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 17:25
von marian
Thanks a lot!
I have to find whether this command is possible in IP-Symcon.
Is there also a command to find out the status - how many commands are still available?

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 17:31
von fsommer1968
At least with homeputer studio an information about the remaining time slots is not available. For information regarding IP Symcon look into the IP Symcon forum: http://www.ip-symcon.de/forum/

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 21.02.2010, 17:43
von marian
I'm on that forum - thanks anyway.

They didn't know correct details about the sending limits, I'll be smart there now :)

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 23.02.2010, 13:23
von marian
Additional question...
The time slot counter is floating (time spent over last hour) or there is a reset every hour?
I hope my question is understandable :)

thnks
Marian

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 23.02.2010, 14:40
von fsommer1968
marian hat geschrieben:Additional question...
The time slot counter is floating (time spent over last hour) or there is a reset every hour?
Marian
The time slot counter should be floating.

I would not take the number of theoretical allowed time slots into account. Keep in mind that the protocol used does not handle collisions. As more datagrams are sent the probability of collisions of all of your senders and possible data loss increases. Therefore keep the number of datagrams as low as possible, to ensure, that there will be less collisions.

Re: FHZ 1300 Sende Begrenzung - in English

Verfasst: 23.02.2010, 14:56
von marian
Thnks.

In general, I keep them low.
However, as you write, commands sometimes don't get through and there's no way of knowing.
It's annoying in some cases (e.g. when turning the light on fails).

Therefore my idea is to have a floating counter of commands sent over last hour and if the number is small (so I have enough time slots available), to repeat some commands with random delay.
I should note that I use PC & FHZ1300PC heavily, as I include the logic of the type "if it is a daytime for children", etc.