Which timestamp type is used with DCM

The timestamp is a 64-bit signed integer representing the offset since Jan 1st, 1601 UTC in 100ns units.

This is the standard used by Windows file timestamps:
https://docs.microsoft.com/en-us/windows/desktop/sysinfo/file-times

Example of data with DCM timestamp:

'{ "v" : [ { "ts" : 131940300990580000 , "Wheel" : 3163 },{ "ts" : 131940301000680000 , "Wheel" : 3163 },{ "ts" : 131940300990580000 , "GreenButton" : 0 },{ "ts" : 131940301000680000 , "GreenButton" : 0 },{ "ts" : 131940300990580000 , "RedButton" : 0 },{ "ts" : 131940301000680000 , "RedButton" : 0 },

AWS and Azure Dataservers offer the possibility of choosing a different timestamp format.