DS1307 Clock Module Skipping Time

I have hooked up a DS1307 clock module to the AXE091U and programmed it to display the time on the screen however for some odd reason the time skips. Watching the seconds on the screen it skips about 15 odd every now and then. Additionally the seconds go up to 90 which is a bit questionable. I'll link my program to be looked over. Any response is appreciated.

Thanks

Time Set:
i2cslave %11010000, i2cslow, i2cbyte
writei2c 0, ($00, $25, $0A, $13, $0B, $0F, $00, $00)
end

Time Display:
i2cslave %11010000, i2cslow, i2cbyte
Hoop:
wait 3
serout b.3,n2400,(254,1)
Command:
readi2c 0, (b0, b1, b2)
pause 50
serout b.3,n2400,(254,128)
pause 50
serout b.3,n2400,(#b2,":",#b1,":",#b0)
pause 50
goto Command

are you travelling at 88 miles an hour? or in a big blue box?

However, have you tried replacing the module as I have come across issues before where the chip itself has become corrupted and outputting incorrect data

The problem is that the data returned from the DS1307 is BCD encoded but you are displaying it as if pure binary.

How would you suggest I fix that?

You need to mask out any bits which are not required then convert the value obtained to a decimal value. There are quite a few discussions on how to do that on the forum including -

http://www.picaxeforum.co.uk/showthread.php?21281-DS1307-decimal-and-BCD-confusion