#2 Read Range tool and other problems

[tcz8]

Hello, I'm new to BACnet. Im still trying to wrap my head around the whole thing. I read too mucn and there is still too much to read! If someone could give me a few nudges in the right direction I would REALLY appreciate it.

In the past few days I've been working on a linux script to get some logs into our database for a website we are building. I have hit a few bumps and after googling for a good while I'm still not sure what would be the best or proper way to handle them.

The current setup:
Right now I'm using bacepics. I'm parsing / formatting the results and storing everything in our DB but the process is really slow.

The Bumps:
1- Why do I sometime have ADPU timeouts when launching the bacepics tool? Its pretty much random, I retry and it works just fine. I setting BACNET_APDU_TIMEOUT=12000 but all it still happens. There is no network issues reaching the BACnet/IP device. Not sure how to trouble shoot this.

2-This is WAY too slow. For the values I just need every 10 minutes its fine, but some sensor data will need to be updated every 5 to 30 seconds. At firs they even wanted realtime updates :/ Oubviously bacepics wont cut it, how should I handle this?

3-How do you get to the trendlog data? Everytime I do a read property on log-buffer i get a read access denied, from what I googled I need to use the read range service but there seems to be no tool in the bacnet protocol stack for this. How can I read those from a linux script?

Thank you!

Fred.

[Steve Karg]

I modified the ReadRange demo application to be similar to ReadProperty demo to allow getting the trend log buffer data:
https://sourceforge.net/p/bacnet/code/2777/

However, the data that is returned is not printed yet as that decoding is not yet supported in the library. Hopefully I'll get it added soon.

[Steve Karg]

APDU timeout can happen if there are more than one application using the same BACnet/IP UDP port. If more than one application is needed at the same time, run the bacserv demo, which has a BBMD inside it, and then have each client application use a different UDP port and register as Foreign Devices to the bacserv application.

[Steve Karg]

To get specific data faster, just use ReadProperty demo (bacrp) for the specific data that is needed, or ReadPropertyMultiple (bacrpm) if the device supports ReadPropertyMultiple service. Additionally, caching the device address bindings will speed up acquisition (see address_cache explained in readme.txt file).

[Anonymous]

READ ACCESS DENIED LOG BUFFER ERROR, HOW TO SOLVE IT

[Steve Karg]

The Log Buffer property values can only be read by ReadRange service, not ReadProperty or ReadPropertyMultiple service.