Hello,
I am designing a system in which I need to generate a timestamp in order to insert a checksum, an ID, and other metadata to accompanying data being passed between modules. I have seen and read of recommendations to use TOY (Time of Year) Chips but I cannot find any specific chip or Datasheet on any, to accomplish this.
Any recommendation or referral to suitable references would be appreciated.
Thanks!
Maxim makes a line of real-time clocks:
as do TI, ST, and others. Search "real time clock" on DigiKey. Will any of these work?
d.
Start with the Maxim DS1305 or DS1307. There are many RTC (real time clocks) out there, so I'm not suggesting this is the best fit for your application. But, at least it will get you started. I think Epson also makes RTC. And you can browse Digikey, Mouser, etc.... to find more.
Good luck. -mpm
An RTC chip, such as the Dallas (now Maxim) DS1307 or its relatives. It handles power management on its own, just toss on a small lithium cell.
Some microcontrollers do have built-in RTCs that can continue to run while the main processor is sleeping. A separate clock chip gives a bit more choice as to what processor to use.
You'll probably not find any with exactly your (unspecified) TOY format, so expect to do a little arithmetic to get the output to the correct layout for your app.
-- Rich Webb Norfolk, VA
Dallas (now Maxim) once dominated the market for real-time clocks:
But TI, ST and others are there, too. Search DigiKey, Newark, etc. for "real time clock".
NXP has many of such chips!
-- Failure does not prove something is impossible, failure simply indicates you are not using the right tools... nico@nctdevpuntnl (punt=.) --------------------------------------------------------------
If you want to generate a unique value from the time stamp, you must be careful how you got that time stamp.
Local time is clearly out of the question in countries using daylight saving time, since going back from daylight saving time to normal time, will cause one hour of duplicate time stamps (I hope I got this right also for the southern hemisphere :-).
UTC is in principle better, but it still suffers from the leap second problem. While in practice all leap seconds have always been added: Dec 31 23:59:59, 23:59:60, Jan 1 00:00:00 UTC but in principle it is also possible to have Dec 31 23:59:58, Jan 1 00:00:00 UTC transition, so depending on the internal representation, there might be duplicate problems.
A truly linear time scale, such as GPS time is safe.
d.
Weird - I thought I replied, but it's not showing up. Did you look at Maxim DS1305 and/or DS1307 yet? Or search on Digikey, Mouser, etc... for Real Time Clock.
ElectronDepot website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.