Of all things, the palmtop I use a lot uses DRAM as it's main RAM - I
was CONVINCED this was SRAM, but it's not.  1/2Mb per chip, and I have 2
(1 Mb) pairs sitting here waiting for a future project.  These're
Hitachi RAM, set in TSOP Left & Right sets (reversed pinout for one -
you can Bus the tri-state pins this way) - Interesting stuff.  So I now
know that it's quite possible, WITH the right RAM, to go decently low
power (2 weeks off 2 1300mAh NiMH batt's with the rest of the machine
running off the same batteries) - Sorta shocked ME!  If I keep upgrading
these machines, someone could talk me out of a pair, certainly you could
talk me out of part numbers (KM416V256ALLTR is the reversed one) - I can
find the other number if you cannot get there from here <G>

I have some info I can dig out that may show how they handle the refresh
process, too.

  Mark

Harold Hallikainen wrote:
>         There have been lots of discussions about serial SRAM on the list over
> the years. As far as I can tell, there aren't any of any significant size
> out there. I WAS using the Dallas RamPort (DS1380 and DS1381) 'til they
> discontinued them on us...  I'm now moving designs over the the PIC18c452
> which has enough RAM for several products. On one product I'm using the
> 18c452 with several latches to drive a 128kbyte SRAM (capacitor backed).
> That takes several chips. Seems like SOMEONE would make a reasonably
> large serial SRAM, but that doesn't seem to be the case.
>
> Harold
>
> On Fri, 2 Jun 2000 09:11:59 +0200 TOM THERON <mmsesys@ICON.CO.ZA> writes:
> > PCF8570 from Philips,  256 x 8,  i2c interface.
> >
> > Tom
> >
> > ----- Original Message -----
> > From: Bob Ammerman
> > To: PICLIST@MITVMA.MIT.EDU
> > Sent: Friday, June 02, 2000 4:18 AM
> > Subject: [PIC]: External SRAM on PIC (or AVR)
> >
> >
> > Just a dumb question: Serial RAM? I've heard of search EEPROM and
> > serial
> > FLASH. I have had a couple applications where serial RAM would have
> > been a
> > godsend. Does anybody make this? What capicity?
> >
> > Thanks,
> >
> > Bob Ammerman
> > RAm Systems
> > (high function, high performance, low level software)
> >
> >
> > ----- Original Message -----
> > From: Bennett, Matt <Matt.Bennett@ANDREW.COM>
> > To: <PICLIST@MITVMA.MIT.EDU>
> > Sent: Thursday, June 01, 2000 11:38 AM
> > Subject: [PIC]: External SRAM on PIC (or AVR)
> >
> >
> > > If you've used the external SRAM (as in STATIC, not serial) on a
> > PIC or
> > AVR-
> > > which SRAM did you use?  I'm having problems finding a 64Kx8 part
> > that is
> > > pin compatible (without gates other than an address latch) and is
> > in stock
> > > somewhere.  I could go to a 2 32K SRAMs, but I'd rather not.
> > >
> > > The PIC (17C) uses an ALE, /OE, /WR scheme, and the AVR uses an
> > ALE, /RD,
> > > /WR scheme.  The PIC appears compatible with the 61XXX family of
> > SRAMs
> > (64Ks
> > > are currently being made of Unobtanium [Un]), but in my brief
> > search, I
> > > haven't found any that are directly compatible with the AVR's
> > scheme.
> > > Serial RAMs are not an option, due to speed issues.
> > >
> > > Matt Bennett
>
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