At 20:02 6.5.1998 -0700, Bob Newhart wrote:
>Does anyone know of a serial static RAM I could use for additional PIC
>data memory?  I am attempting to alter a pre-existing design that uses
>93C66 EEPROMs, so something with the same pinout and bit-banging scheme
>would be nice, although not absolutely necessary.  I don't care whether
>the SRAM is volatile or not.
>
>The only firm requirements are three pin interface, minimum 64 bytes RAM
>per chip (bigger is better), and no write cycle limitations like those
>associated with EEPROM and FLASH.
>
>Bonuses would be:
>     256 bytes per chip
>     nonvolatile
>     8 pin package with pinout similar to 93C66 EEPROM
>

As I already wrote. I used PCF8583 in one of my projects. These chips are
date/clock/alarm chips with 240 bytes of RAM and I2C interface. You can use
up to 2 chips on one I2C bus, so you can get 480 bytes of RAM. Clock and/or
event counter is a free bonus. I also used MAX690 as a watchdog chip, with
one small lithium battery as a backup for RAM content. Works without any
problem. Only sad think is that you need place for I2C routines.

Best regards

PavelK

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* Pavel Korensky                                                         *
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* SUMMA SCIENTIA - NIHIL SCIRE                                           *
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