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Design files:
https://fake-server.no-ip.org/svn/FPGAStuff/DAQ%20systems/
(In the "GPS Timestamp" series of directories).

Design files:
https://fake-server.no-ip.org/svn/FPGAStuff/DAQ%20systems/
(In the "GPS Timestamp" series of directories).
(Note: Files are from Altium Designer. The are not eagle files).

Something is going on with my SVN server at the moment, and anonymous login isn't working, so I can't post links to the source and board files. When I get it fixed, I'll edit that in.

Design files:
https://fake-server.no-ip.org/svn/FPGAStuff/DAQ%20systems/
(In the "GPS Timestamp" series of directories).

Source code:
https://fake-server.no-ip.org/svn/Programming/Code/AVR/
Again, in the "gpsTimeStamp" series of directories.

Basically, I work in a research lab, and we often have instruments that have multiple independent data-acquisition systems. We need to be able to correlate the time at which samples from each system were taken, which can be difficult if you want to resolve sampling-times to a great degree of precision. Using something like a USB data-acquisition system, just the USB latency can introduce several hundred milliseconds of unknown latency, that can vary from acquisition to acquisition.

I did some long-duration testing between two of the ATmega2560 boards, and over 72 hours, the RMS time-error between the two units was ~20 uS. My design goal was < 1 ms, so I'm pretty damn happy with that.

Basically, I work in a research lab, and we often have instruments that have multiple independent data-acquisition systems, which can be physically separated by as much as 50 feet. We need to be able to correlate the time at which samples from each system were taken, which can be difficult if you want to resolve sampling-times to a great degree of precision. Using something like a USB data-acquisition system, just the USB latency can introduce several hundred milliseconds of unknown latency, that can vary from acquisition to acquisition.

I did some long-duration testing between two of the ATmega2560 boards, and over 72 hours, the RMS time-error between the two units was ~20 uS. This was with two completely independent antennas too. My design goal was < 1 ms, so I'm pretty damn happy with that.