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7. “USB” - Micro USB ports is needed for USB camera recording, USB Flash for system logs, and system restoration. Read instructions in "Connecting USB camera", "USB camera settings. How to save a video", "Saving system logs on USB flash drive", and "USB upgrade or restore of default settings".
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12. "DRY CONTACT INPUTS 1...16" - Digital inputs (Type IN). Read the instructions at "Connecting dry contacts", and "Dry contacts settings".
13. “Extension slot” - Only one of the two extensions can be installed “VT485m / Modbus RTU extension” or “VT485r / OSDP v2 reader extension”. Ordered separately.
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