Le 10/12/2012 13:44, Chris Howard a écrit :
If it were me, I'd suspect that my window of bits is off
to the left or right by one bit. The old "first bit is
called zero" problem.
And the relationship between 7-> 3 and 5-> 1 makes me
wonder.
Chris
On 12/10/2012 5:00 AM, Tom Harris wrote:
I am logging the data from this strange master clock, and the none of the
bits 42 through 44 are stuck. Good idea, though. I have just checked
tonight, and the DOW is indicating as 5 (Friday), despite it only being
Monday.
Good idea though.
I guess you will need to log a weeks worth to see if there is a logical
pattern.
How about flipped bit 44 ? That would give the seen Sunday and Monday
values. Tomorrow would be 6.
Mon = 101 5
Tue = 110 6
Wed = 111 7
Thu = 000 0
Fri = 001 1
Sat = 010 2
Sun = 011 3
The parity being good may mean that it is not an error, but a feature.
On 9 December 2012 23:24, mike cook <[email protected]> wrote:
Le 09/12/2012 11:28, Tom Harris a écrit :
Greetings Time Nuts.
Time related, but unusually so:
I am examining the DCF77 (see
http://en.wikipedia.org/wiki/**DCF77<http://en.wikipedia.org/wiki/DCF77>for a
refresher) data output from a master clock intended to drive a series of
slave clocks operated from 24V DC, interrupted by 100ms or 200ms pulses to
signal '0'& '1' on the data. What I am seeing is that the "day of week"
bits 42 through 44 inclusive do not code the day correctly, they seems to
have a variable offset from the actual day, I have seen an offset from +1
to +3. The rest of the data, ncluding parity bits, are OK. Today,
9/12/2012, the day is Sunday, which should be coded as '7'. However I am
seeing a value of '3', which is Wednesday.
Is this normal, do wired DCF77 slave clocks transmit munged dow data to
prevent them being used with someone else's master clock? If they do I am
hosed since I am trying to reverse engineer the master clock.
Is it just bit 44 being stuck on zero? or can each dow get varying
values?
--
Les chiens aboient, et la caravane passe.
______________________________**_________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/**
mailman/listinfo/time-nuts<https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts>
and follow the instructions there.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
--
Les chiens aboient, et la caravane passe.
_______________________________________________
time-nuts mailing list -- [email protected]
To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
and follow the instructions there.
