Hardware+ Sorftware Time Synchronization

[Elvis8]

Hi everyone!
I need help in a project:
I need that the date and time that is in the computer and in a PIC 16F877A with an RTC, become synchronized. No matter if the PIC is at a very large distance from the computer, the date and time must be the same in both.
I will appreciate your help and ideas!

 

[klystron]

How accurate do you want to synchronize the times ?

 

[horace1]

hpw long do you require the time to be accuarate for and, as klystron asked, what do you mean by accurate ?
For example, if a life time of 5 to 10 years and accurate to a few second is sufficent a battery backed RTC such as the Ramtron FM33256 or Microchip MCP79410 would be OK.
Alternativly if you have a GPS device attached you can get the time from the NMEA data or if you have a TCP/IP enabled GSM modem you could get the time from a time server.

 

[Elvis8]

I want the synchronization the most accurate it can be. And I was thinking on getting the time from the NIST,but I dont know how the PIC can receive the internet signal at the same time a computer receives.

 

[horace1]

if you are in range of a WiFi network you could use TCP/IP to connect to NIST otherwise a TCP/IP GSM modem could be used.