They actually do, I noticed this when logging some CGate messages in PICED and saw on a Comfort startup I get a message in PICED stating that it relinquish control to Comfort's broadcast.
The descision on who is more accurate than the other is purely a hardcoded method. HomeGate is more accurate than a PAC for instance. Clipsal makes some assumtions that HomeGate running on a PC is probably NTP sync'd and a PAC is running of it's internal clock. A good description is in the PICED/HomeGate help file.
Yes, once someone changes the time manually then that device will probably become the Master at that time, further updates from that point will probably follow the broadcast interval again and whoever is more frequent will eventually be selected as the Master again. If I however set time manually, say every 10 minutes, on a unit then it stands to reason that I will be the time master until I stop updating the time manually.
On the otherhand, even if Comfort keeps on sending time it doesn't really matter because Comfort accepted time from the more acurate time source anyway. The problem with this is that 60 minutes is also the shortest interval from the Cbus side so it would have relinquished control to Comfort and NOT update time anymore. Comfort would end up being the only time source. If Cbus had something that sent more frequently than 60 minutes then all would be ok. Saying this, with two devices sending at the same interval it is just fate who will be the time master at that point in time, it probably depends on who starts-up first on a reboot - who knows.
Ingo
Last edited on Saturday Jul 3rd, 2010 08:47 am by Ingo
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