Searching \ for '(OT) Timekeeper (R) RAM alternative ?' 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/timers.htm?key=time
Search entire site for: 'Timekeeper (R) RAM alternative ?'.

Truncated match.
PICList Thread
'(OT) Timekeeper (R) RAM alternative ?'
1999\05\13@120647 by MEDICINTEKNIK KB

picon face
I use the Timekeeper (R) RAM in a PIC project (so this is just a little off topic - OK ?) The advantage is a classic, useful scratchpad, with a 10 year clock on top (year month ....) both are very valuable for this project. The disadvantage is, that the 32 K memory needs 15 addresslines, and thus a hairy PCB. Either I need to use latches or drivers (or use up the I/O ports of the PIC) to address this special RAM.

Now - have anyone of you seen a serially (SPI ??) addressable RAM / timer combination out there ?

Best Regards

Sven

1999\05\13@171440 by Barry King

flavicon
face
ST Microelectronics makes the M41T11, its a I2C clock calendar plus
56 bytes of RAM.  It has all the backup battery switching built in,
but not the battery itself.  It uses a watch crystal and has a cool
digital calibration trick to do accuracy trim.

They have a web site, but I don't have the URL handy.  AltaVista can
find 'em.

------------
Barry King, KA1NLH
Engineering Manager
NRG Systems "Measuring the Wind's Energy"
Hinesburg, Vermont, USA
spam_OUTbarryTakeThisOuTspamnrgsystems.com
"The witty saying has been deleted due to limited EPROM space"

1999\05\14@234407 by Leo TImmer

flavicon
face
Philips offers the PCF8553 clock/calendar with 240*8bit ram and the PCF8593
low power version with 8byte ram. Try
http://www-us.semiconductors.philips.com/
Leo
<.....salsaterKILLspamspam@spam@dds.nl>


----------
> From: MILTON MEDICINTEKNIK KB <milton.medicinteknikspamKILLspamTELIA.COM>
> To: .....PICLISTKILLspamspam.....MITVMA.MIT.EDU
> Subject: SV:   (OT) Timekeeper (R) RAM alternative ?
> Date: Thursday, May 13, 1999 6:08 PM
>
> I use the Timekeeper (R) RAM in a PIC project (so this is just a little
off topic - OK ?) The advantage is a classic, useful scratchpad, with a 10
year clock on top (year month ....) both are very valuable for this
project. The disadvantage is, that the 32 K memory needs 15 addresslines,
and thus a hairy PCB. Either I need to use latches or drivers (or use up
the I/O ports of the PIC) to address this special RAM.
>
> Now - have anyone of you seen a serially (SPI ??) addressable RAM / timer
combination out there ?
>
> Best Regards
>
> Sven

1999\05\16@225739 by John Duncan

picon face
I
>I use the Timekeeper (R) RAM in a PIC project (so this is just a little
off topic - OK ?) The advantage is a classic, useful scratchpad, with a 10
year clock on top (year month ....) both are very valuable for this
project. The disadvantage is, that the 32 K memory needs 15 addresslines,
and thus a hairy PCB. Either I need to use latches or drivers (or use up
the I/O ports of the PIC) to address this special RAM.
>
>Now - have anyone of you seen a serially (SPI ??) addressable RAM / timer
combination out there ?
>
>Best Regards
>
>Sven
>
>

I am developing a project using the Dallas Semiconductor DS1307 RTC.  56
bytes of battery backed RAM and I2C bus.

Cheers
JD

1999\05\17@004740 by Tjaart van der Walt
flavicon
face
Leo TImmer wrote:
>
> Philips offers the PCF8553 clock/calendar with 240*8bit ram and the PCF8593
> low power version with 8byte ram. Try
> http://www-us.semiconductors.philips.com/
> Leo

It is a nice chip, but watch out - if you inadvertantly
write '11' to the setup bits, you're screwed. '11' Puts
the chip into a test mode, and you have to power-cycle
it to get it to recover. This 'feature' is pretty
dangerous if you have a volume application.

--
Friendly Regards          /"\
                         \ /
Tjaart van der Walt        X  ASCII RIBBON CAMPAIGN
EraseMEtjaartspam_OUTspamTakeThisOuTwasp.co.za  / \ AGAINST HTML MAIL
|--------------------------------------------------|
|             Cellpoint Systems SA                 |
|             http://www.cellpt.com                |
|--------------------------------------------------|
|     http://www.wasp.co.za/~tjaart/index.html     |
|Voice: +27-(0)11-622-8686  Fax: +27-(0)11-622-8973|
|          WGS-84 : 26¡10.52'S 28¡06.19'E          |
|--------------------------------------------------|

1999\05\17@010203 by Dennis Plunkett

flavicon
face
At 07:02 17/05/99 +0200, you wrote:
{Quote hidden}

Hey, Tjaart; why should there be a difference between a one off application
and a "Volume" application in this case?
Nasty features like that can cause trouble at any point in time. Could be
interesting if your micro has taken a long walk of a short pier into the
inevitable bliss of electronic wonderland. There be no recovery for this
one opps, no defensive code recovery eh?

Dennis

1999\05\17@015710 by Tjaart van der Walt

flavicon
face
Dennis Plunkett wrote:
{Quote hidden}

Well, if you are watering your garden with it, you'll
notice it soon enough (slop, slop). If you have an
installed base of a few thousand or more, you had better
get to the airport.... ;)

I have tried everything (software wise) to get it to
recover, but it won't. Period. I have built-in checks
at two different levels to prevent this from happening
in my software.

--
Friendly Regards          /"\
                         \ /
Tjaart van der Walt        X  ASCII RIBBON CAMPAIGN
@spam@tjaartKILLspamspamwasp.co.za  / \ AGAINST HTML MAIL
|--------------------------------------------------|
|             Cellpoint Systems SA                 |
|             http://www.cellpt.com                |
|--------------------------------------------------|
|     http://www.wasp.co.za/~tjaart/index.html     |
|Voice: +27-(0)11-622-8686  Fax: +27-(0)11-622-8973|
|          WGS-84 : 26¡10.52'S 28¡06.19'E          |
|--------------------------------------------------|

1999\05\28@182252 by MEDICINTEKNIK KB

picon face
Thanks, but not exactly what I needed. I would like to combine the timer with a 8 KB RAM.

However... I agree with you that this looks nice. I might rec—nsider the design.


Kindest regards

Sven
-----Ursprungligt meddelande-----
FrŒn: John Duncan <KILLspamj.duncanKILLspamspamBOM.GOV.AU>
Till: RemoveMEPICLISTTakeThisOuTspamMITVMA.MIT.EDU <spamBeGonePICLISTspamBeGonespamMITVMA.MIT.EDU>
Datum: den 17 maj 1999 04:57
€mne: Re: SV: (OT) Timekeeper (R) RAM alternative ?


{Quote hidden}

More... (looser matching)
- Last day of these posts
- In 1999 , 2000 only
- Today
- New search...