DT-INt and Interrupt on Change

[Darrel Taylor]

Since there's nothing in the ISR that uses PBP's SYSTEM variables, change the TYPE of interrupt to ASM for faster execution.

[Luckyborg]

Tried the asm version, also increased clock speed form 40 to 64 MHz. I was able to get some data at 4800, but not reliable. Thanks for helping though

David