Searching \ for 'Serial (SPI or I2C) SRAM' in subject line. ()
Make payments with PayPal - it's fast, free and secure! Help us get a faster server
FAQ page: techref.massmind.org/techref/i2cs.htm?key=i2c
Search entire site for: 'Serial (SPI or I2C) SRAM'.

Truncated match.
PICList Thread
'Serial (SPI or I2C) SRAM'
1998\11\18@162420 by nanthan Paramananthan

flavicon
face
Does anybody know a large Serial (SPI or I2C) Static RAM (SRAM)
manufacturers.

I am trying to interface it to the PIC and I don't want to use parallel
version which will take up one whole port just for RAM instead of 2 for I2C.

I am looking for at least  32k X 8.

Thank you.

S. Paramananthan

1998\11\18@175418 by Jason Tuendemann

flavicon
face
Check out http://www.microchip.com/10/Lit/Memory/index.htm for Microchips
chips. But atmel make a large SPI flash ram which seems it could be a good
thing, I have a couple to try but as yet have not had time. They are
AT45D041 4 megabit 5 volt serial flash and ATD161 16 Megabit 5Volt serial
flash. Although i have not been able to get hold of the 16Mb chip as yet.
All data sheets are on the Atmel site. There is/was a site http://www.questlink.com
which was great but I can't seem to get onto it. But you can search for
alsorts of devices and get the data sheets.

Hope this helps
Jason


>Does anybody know a large Serial (SPI or I2C) Static RAM (SRAM)
>manufacturers.
>
>I am trying to interface it to the PIC and I don't want to use parallel
>version which will take up one whole port just for RAM instead of 2 for
I2C.
>
>I am looking for at least  32k X 8.
>
>Thank you.
>
>S. Paramananthan
>
>

1998\11\19@055431 by nanthan Paramananthan

flavicon
face
Hi Jason,

Thank you for your e-mails.

I'm afraid they don't have Serial SRAM, They do however have Flash Memory &
EEPROM.

I'm particularly looking for SRAM because I don't want 7 -10ms time delay
while writing data.  PIC has limited RAM but I need lot RAM for my signal
processing project.

Thank you.

Best regards
Saba




{Original Message removed}

1998\11\19@120744 by Harold Hallikainen

picon face
On Thu, 19 Nov 1998 01:28:41 -0000 Sabananthan Paramananthan
<spam_OUTsabananthanTakeThisOuTspamdial.pipex.com> writes:
>Hi Jason,
>
>Thank you for your e-mails.
>
>I'm afraid they don't have Serial SRAM, They do however have Flash
>Memory &
>EEPROM.
>
>I'm particularly looking for SRAM because I don't want 7 -10ms time
>delay
>while writing data.  PIC has limited RAM but I need lot RAM for my
>signal
>processing project.

       The lack of serial RAM chips for use with the PIC has been a
problem for years.  I finally went with the Dallas RamPort for existing
projects, but could still use a serial RAM.  The RamPort is only 2Kbytes
and uses 11 I/O lines (though it repeats 8 of them so they can continue
to be used as I/O lines).
       SOMEBODY otta make BIG (32 K bytes or more) serial RAM!


Harold




Harold Hallikainen
.....haroldKILLspamspam@spam@hallikainen.com
Hallikainen & Friends, Inc.
See the FCC Rules at http://hallikainen.com/FccRules and comments filed
in LPFM proceeding at http://hallikainen.com/lpfm

___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]

1998\11\19@170529 by John Payson

flavicon
face
|        The lack of serial RAM chips for use with the PIC has been a
|problem for years.  I finally went with the Dallas RamPort for existing
|projects, but could still use a serial RAM.  The RamPort is only 2Kbytes
|and uses 11 I/O lines (though it repeats 8 of them so they can continue
|to be used as I/O lines).

You may want to check out http://www.ramtron.com for information about
their "FRAM" products.  They may fit your needs nicely.  They
offer moderate-sized (2Kx8) non-volatile I2C/SPI memories in an
8-pin package at reasonable prices.

Advantages over EEPROM devices:
 10^13 write cycle endurance
 Writes happen immediately, as fast as you clock in data

Disadvantages over EEPROM devices:
 10^13 read cycle endurance (actually 10^13 writes + reads)
 Writes happen immediately, as fast as you clock in data

Note that unlike EEPROMs, which will hold a number of bytes in
a "page" buffer until a valid I2C "stop" is received, and which
will disregard any attempted write operation which does not end
with a properly-placed stop condition, the FRAM devices write
each byte of data immediately following the acknowlege pulse.
As a consequence, it is possible for much or all of the device
to get accidentally overwritten if the CPU behaves badly under
power-down conditions.

For your application, though, it sounds as though the FRAM devices
may be quite adequate.  Visit <http://www.ramtron.com> for more
information.


Attachment converted: wonderland:WINMAIL.DAT (????/----) (0001E76F)

1998\11\26@024804 by jmnewp

flavicon
face
I have also been looking for serial sram to use with a data aquisition
application.  I would like to read an A/D then store it in sram really
fast, how fast are the fastest sram chips that you have seen and what
are they?  Thanks.

Jon Newport



Sabananthan Paramananthan wrote:
{Quote hidden}

1998\11\27@151029 by mkeitz

picon face
On Thu, 26 Nov 1998 01:59:12 -0800 MARK D NEWPORT
<jmnewpspamKILLspamworldnet.att.net> writes:
>I have also been looking for serial sram to use with a data aquisition
>application.  I would like to read an A/D then store it in sram really
>fast, how fast are the fastest sram chips that you have seen and what
>are they?  Thanks.

Most of the serial flash chips can accept data much faster than a PIC
could send it (megabits per second) because they use a page write scheme
which writes a couple hundred bytes at a time.  But since it is flash not
SRAM you have to wonder about wearout if the writing is constantly
repeated.  The manufacturers seem reluctant to quote a life expectancy in
their data sheets.

___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]


'Serial (SPI or I2C) SRAM'
1998\12\04@012605 by Mike Keitz
picon face
On Thu, 26 Nov 1998 01:59:12 -0800 MARK D NEWPORT
<.....jmnewpKILLspamspam.....worldnet.att.net> writes:
>I have also been looking for serial sram to use with a data aquisition
>application.  I would like to read an A/D then store it in sram really
>fast, how fast are the fastest sram chips that you have seen and what
>are they?  Thanks.

Most of the serial flash chips can accept data much faster than a PIC
could send it (megabits per second) because they use a page write scheme
which writes a couple hundred bytes at a time.  But since it is flash not
SRAM you have to wonder about wearout if the writing is constantly
repeated.  The manufacturers seem reluctant to quote a life expectancy in
their data sheets.

___________________________________________________________________
You don't need to buy Internet access to use free Internet e-mail.
Get completely free e-mail from Juno at http://www.juno.com/getjuno.html
or call Juno at (800) 654-JUNO [654-5866]

1998\12\07@021715 by Dr. Imre Bartfai

flavicon
face
Hi,
there is an SRAM from Philips, I guess PCF8570 or 8750 or similar.
However, it has a limited storage size... :-(

Imre


On Fri, 27 Nov 1998, Mike Keitz wrote:

{Quote hidden}

More... (looser matching)
- Last day of these posts
- In 1998 , 1999 only
- Today
- New search...