The UC-500 has a call accounting feature which you can enable it via CCA (Please refer to image)
You will need an FTP server to which you can upload the information to, and this will give you CDR (Call Distribution Records) and you can then pass them into what ever system you want or read it as a raw file, either one can work quite well.
Surprisingly this to me seems to a very much unused feature although it holds a lot of usefull information in it
Hope this helps you out...
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