I posted two examples in the "Code Examples" section that show how to make accurate clocks using polling of TMR0. You could switch to TMR1 with a little effort - Look for "Easy and Accurate Clocks without RTC IC"

The example programs require a 4.000MHz Crystal, use TMRO, but do not require preloading counters. Although pollling is used, you have over 65mSec to do other stuff before needing to return to your overflow check (polling routine). The programs are short as well. Good Luck.

Paul Borgmeier
Salt Lake City, Utah
USA