🚀 go-pugleaf

John Fields wrote:
> 
> On Fri, 7 May 2004 19:22:25 +1000, "Darrin" <darrin_2000au@yahoo.com>
> wrote:
> 
> >To those in the know:
> >I am after designing a Real-Time Clock circuit with 8 Data output lines,
> >such that at a specific time of the day it should output a set pattern of
> >data on its output, hold this data at the outputs for exactly 3 hours, then
> >revert to default (defined) for the rest of the day. Further, this change
> >should only happen during weekdays and not weekends or public holidays. I am
> >hoping to achieve this by using a RTC chip.  I am presently looking at a
> >chip which I believe may be able to do this (RTC-62421). Has anyone used
> >this chip before or have any information like datasheet, specs etc...? Any
> >ideas or suggestions appreciated.
> 
> ---
> I've used a Dallas/Maxim DS1307
> 
> http://pdfserv.maxim-ic.com/en/ds/DS1307.pdf
> 
> for a similar application, and used its internal 56 X 8 non-volatile
> (battery backed-up) memory to hold the data.  It communicates over a
> two-wire bidirectional bus, so you'll need a �C of some flavor to talk
> to it.  One nice thing about it, IIRC, is that with a 7.5mAH lithium
> battery for backup it'll keep time _and_ retain the data written into
> its RAM for over 10 years.
> 
> --
> John Fields


DS1305 is one I use.