More RTC

Started by omtispr August 25, 2004
First thanks Tom Becker for your answer to our question but your
solution don't sound logic to us and we are so sorry o said that. we
know very well the DS1307 rtc chip because we use the chip in designs
before. why if the bx-24 have a rtc we have to add more components to
the desig why we can't use then like or the same way as the DS1307
chip.

jesus aponte
omis
eng



> ... if the bx-24 have a rtc ... why we can't use then like or the same
way as the DS1307 chip?

Because the BX-24 RTC is implemented in OS firmware. It is a count of
512Hz interrupts that are generated by the 8535's Timer0. The BX-24
does not have an autonomous RTC like the DS1302. Tom
Tom Becker
--... ...--
www.RighTime.com
The RighTime Clock Company, Inc., Cape Coral, Florida USA
+1239 540 5700


Why/how would you expect a chip to retain and continually
update a clock/time feature if it's un-powered. The sleep mode
minimizes power consumption and will retain the clock.

The ds1307 needs power continuously as well to maintain its tracking
so it's no different. Remove the power fro mthe DS1307
and it will need to be reset every time you power it up as well.

ptegler
----- Original Message -----
From: "omtispr" <>
To: <>
Sent: Wednesday, August 25, 2004 10:47 PM
Subject: [BasicX] More RTC > First thanks Tom Becker for your answer to our question but your
> solution don't sound logic to us and we are so sorry o said that. we
> know very well the DS1307 rtc chip because we use the chip in designs
> before. why if the bx-24 have a rtc we have to add more components to
> the desig why we can't use then like or the same way as the DS1307
> chip.
>
> jesus aponte
> omis
> eng >
> Yahoo! Groups Links



There is one BIG difference between the RTC in the BX-24 and the DS1307
chips. The
difference is that the BX-24 RTC will return to zero whenever you RESET the
BX-24 even
if power remains on. The DS1307 is made to work with double-layered
capacitors or SuperCaps or
Ultra-Caps. The capacitors act as batteries to provide power to the DS1307
whenever system
power is off. I like using the DS1305 because it also provides 96 bytes of
battery backed RAM.

Chuck
----- Original Message -----
From: <>
To: <>
Sent: Wednesday, August 25, 2004 10:31 PM
Subject: Re: [BasicX] More RTC > Why/how would you expect a chip to retain and continually
> update a clock/time feature if it's un-powered. The sleep mode
> minimizes power consumption and will retain the clock.
>
> The ds1307 needs power continuously as well to maintain its tracking
> so it's no different. Remove the power fro mthe DS1307
> and it will need to be reset every time you power it up as well.
>
> ptegler
> ----- Original Message -----
> From: "omtispr" <>
> To: <>
> Sent: Wednesday, August 25, 2004 10:47 PM
> Subject: [BasicX] More RTC > > First thanks Tom Becker for your answer to our question but your
> > solution don't sound logic to us and we are so sorry o said that. we
> > know very well the DS1307 rtc chip because we use the chip in designs
> > before. why if the bx-24 have a rtc we have to add more components to
> > the desig why we can't use then like or the same way as the DS1307
> > chip.
> >
> > jesus aponte
> > omis
> > eng
> >
> >
> >
> >
> >
> >
> > Yahoo! Groups Links
> >
> >
> >
> >
> >
>
> Yahoo! Groups Links >