Reverse engineer 4 hex values to DateTime

Question

Trying to reverse engineer 4 hex values to DateTime stamp from my heating system

I know that: 5F:A2:30:77 --> 2019.03-10 - 10:08 6D:A2:30:77 --> 2019.03-10 - 10:21

My first guess was that this was Unix timestamp, so converted the HEX to DEC and to a 32bit int = >

5F:A2:30:77 -> 1999675999 equivalent to 2033-05-14T09:33:19+00:00 in ISO 8601 6D:A2:30:77 -> 1999676013 equivalent to 2033-05-14T09:33:33+00:00 in ISO 8601

but unfortunately this does not work

hope that something has a good idea of how to convert this.

Thanks

//Kim

Answer 1

we have solved the riddle of this conversion :-).

byte 1 = Minutes after midnight.
byte 2 = Day of the month.
byte 3 = Month.
byte 4 = Number of years since 1900.

# 2019.03.10 19:38
stamp = int(0x7730A49A)
time = stamp & 0b111111111111
hours = int(time/60)
minutes = time - (hours*60)
day = (stamp >> 12) & 0xFF
month = (stamp >> 20) & 0xF
year = (stamp >> 24) + 1900

Thanks to all who try to help.

Case closed :-)