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https://wiki.teltonika.lt/view/Digital_tachograph_monitoring_and_data_reports
Note
Tachograph files from VDO 4.0 are in "GEN2" format and cannot be opened by regular DDD reader (which only support GEN1 formats). So to open GEN2 files, you need to have GEN2 software.
One of the tachograph file viewer software, which support GEN2 files - https://www.tachosys.com/Downloads/Software --> Tachograph File Viewer 3.05
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Connection and configuration of the tachograph for the FMB640
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