In message  <9611171134.AA21186@zsu.edu.cn> PICLIST@MITVMA.MIT.EDU writes:

> I have a project which needs a battery powered real-time clock (RTC) chip. The
>  chip should have a serial port that can be connected to a PIC16C54. Does any
>  one know where there is such kind of chip, its type and source? Any help is
>  greatly appriciated.

I'm currently developing a genlocked time display for video camera signals,
the clock chip I'm using is the Philips PCF8583P. This is an eight pin I2C
chip, and also includes 256 bytes of EEPROM which can be used for storage.

I've not got it hooked up to a PIC yet, but I've got it connected to my PC,
and with the power disconnected it consumes 2.4uA from a 2.4v nicad.

In the UK it's available from RS Components, or many other sources. It's also
used in a number of VCR's, in particular Grundig ones (with a battery, so the
clock is always running), and in a Sharp TV/VCR (with a capacitor, only gives
a limited backup).

Nigel.

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        | Nigel Goodwin   | Internet : nigelg@lpilsley.demon.co.uk     |
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