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Author Topic: BACNet Over Zigbee  (Read 1303 times)
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Fremont,CA
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Hi All,

I am implementing Automation control network project. Till now I got success to send 512 bytes packet through Xbee,ethernet shield with DHCP feature, some of BACNet features which working very good.
But Actual BACNet (Application layer protocol) protocol is supporting 1472 bytes of packetSize. I am getting hard time increase this packet Size. Till 512 bytes Aggregation and fragmentation through Xbee is working perfectly fine.

But if I use Xbee libraries, DHCP libraries,UDP libraries in my code it works till 512 bytes of packet size. If anybody help me to increase the packet size till 1472 bytes that would be really helpful for me.
Also, if I will not use DHCP libraries  then with static IP it works till 1024 bytes. Here is my main problem.
1. With Xbee and UDP libraries I can only send/receive up to 1024 bytes it is not working more then that.
2. With Xbee,UDP,DHCP libraries It is not working after 512 bytes.
How should I resolve this problem ? Or Do I need to modify the library files?
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Seattle, WA USA
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But if I use Xbee libraries, DHCP libraries,UDP libraries in my code it works till 512 bytes of packet size.
You have, on the Arduino, only 2048 bytes of SRAM. The HardwareSerial class uses some of that. The other libraries use more of it.

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If anybody help me to increase the packet size till 1472 bytes that would be really helpful for me.
Easy. Get a Mega which has 8096 bytes of SRAM.

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Do I need to modify the library files?
Changing the code won't increase the amount of memory you have. Only changing the hardware will help.

Alternatively, you can parse the data as it arrives, rather than trying to store all 1400+ bytes.
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Fremont,CA
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Thank you So much for your reply.
I will try with the mega.
Just wondering to ask you have worked on BACNet? I am trying to make Arduino/ethernetshield/xbee as BACNet/Zigbee wireless router and BBMD.

Again thanks for your help
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Seattle, WA USA
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Just wondering to ask you have worked on BACNet?
No. Never heard of it. I simply recognized what your problem was.
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