Is the parity bit P3 consistent? It protects the day of the month and that of the week.
On Sun, Dec 9, 2012 at 1:24 PM, 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 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 > 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.
