🚀 go-pugleaf

In article <1395@cseg.uucp> gmg@hcx.uucp (Greg M. Garner) writes:
>In article <8519@burdvax.PRC.Unisys.COM>, coltoff@PRC.Unisys.COM (Joel Coltoff) writes:
>> Does anyone know of a real time clock chip that can interface directly
>> to an 8051. Everyone I've seen so far is to slow to interface at 16 MHz.

>How about using the mostek 48T02 real time battery backed static ram?

I have used one of these clock chip/rams for over a year now and am quite
happy with its performance (with a Z-80).  There is no crystal trimmer cap, so
the trimming is done with a special pulse adder/stealer circuit that can be
set to add or subtract pulses every N minutes where N is stored in a special
register.  I have heard that HP uses a similar technique in their HP41
calculator.  The expected lifetime of the lithium cell is about 10 years if
I remember correctly, longer if the chip is usually powered up.

Maybe Mostek could come out with a 32K X 8 Ram with the same clock...

 ^	Forrest Cook   (The preceding comments were my Opinions)	 ^
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