Hi Darrel,

Hmmm, looking at the various timings I don't see how this can be done.

The NMEA string is output at the same point, the epoch of the PPS pulse, so the code is executing the string read when it also needs to start to display the 'advanced' time.

As I see it at the moment, the code reads the gps string, then parses it, saving each piece to the assigned variable and runs the subroutines before initiating the display.

As a test, I added two seconds to the seconds variable. Then comparing against a radio time signal it was almost the same. I say almost as it is not quite two seconds out in code execution.
I suppose I could add a suitable pause value and bring it inline but I would have to test the offset, if any, over a period of operation. This assumes code execution always takes the same time to execute.

Any ideas would be welcome.