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ReadProperty.py on the same device using IP2VLANRouter.py

See original GitHub issue

Hello @JoelBender, @ChristianTremblay. Hope you are doing well. I have two devices A & B. DEVICE A is running IP2VLANRouter.py with 5 and I have run ReadProperty.py and ReadWriteProperty.py samples on DEVICE B. I can detect the devices from ReadProperty.py pr ReadWriteProperty.py on DEVICE B using:

>> python samples/ReadProperty.py --ini BAC0.ini
> read 20:2 analogValue:2 presentValue
15.0233

My question is; - How can I detect them on DEVICE A?

Thanks in Anticipation.

Issue Analytics

State:
Created 3 years ago
Comments:7 (4 by maintainers)

Top GitHub Comments

1reaction

JoelBendercommented, Dec 25, 2020

BACnet is a protocol for device-to-device communications, there is no concept of “send this request to myself”. You can run two different applications on the same machine, like both IP2VLANRouter.py and ReadWriteProperty.py, provided they use different UDP ports. In this case, you have two different devices with two different BACnet addresses on two different BACnet networks.

Before getting too deep into BACnet routing, here is a simple way to get two applications on the same machine to talk to each other:

create an INI file called BAC0.ini and put 192.168.0.118/24:47808 in the address field and give it device instance number 1234.
in a terminal window, run python ReadWriteProperty.py --ini BAC0.ini
create a second INI file called BAC1.ini and put 192.168.0.118/24:47809 in the address field and give it device instance number 5678.
in a second terminal window, run python ReadWriteProperty.py --ini BAC1.ini

You now have two applications with two different UDP ports on the same machine and they can talk to each other.

in the second window, enter read 192.168.0.118:47808 device:1234 objectName and it will return the device name (which is a common shortcut of saying “the object name of the device object in the device”).
in the first window, enter read 192.168.0.118:47809 device:5678 objectName and it will return the other device name.

In both of those cases the application in one window is talking to the application in the other window using BACnet. What is different about BACnet than what you might be expecting is that the two applications are peers and can exchange content between them in both directions at the same time.

0reactions

anas-r-devcommented, Dec 28, 2020

It’s working now. Thank you @JoelBender

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