Defer assigning the decoded time until the minute length has been checked to match the exact expected value (i.e. 59 unless a leap second occurs).
Defer assigning the decoded time until the minute length has been checked
to match the exact expected value (i.e. 59 unless a leap second occurs).

This (significantly) reduces the amount of false time jumps in case a bit
gets split up due to a reception error.

rene0/dcf77pi,rene0/dcf77pi