Now that it is not 2Am, I see that it might be the PAUSEUS line - PAUSEUS has a minimum delay of 24uS when used with a 4 MHz XTAL. I also took "your" comments about the delay loop as being accurate at 1 mS. I will check that as well.

What XTAL speed are you running?

Unfortuantely, it is "Off to Grandma's House" here as it is a major holiday. I will not have a minute to debug until tomorrow night (36 hours from now). As asked before,

Anyone else have an opinion on the ASM to BASIC conversion or want to take a stab at the problem? If not, I will revisit when I return.