Okay, I'm understanding a bit more. One trick is you must EXEC PROGRAM 2 not 1. Neither Register shows any life or more than a single Zero on display (is there additional formatting?) The toggle rate between registers is pretty slow unless I put the probe on something with some activity then the toggling between displaying REG0 and REGF speeds up. new listing.... :code :setup active force off :setup active interrupt off :setup beep on /* ************************************************* * This program turns the Fluke 9010A into a * * < 4Mhz FREQUENCY COUNTER * ************************************************* */ :equate frequency as 1 :equate count.test as :next :program count.test label 3 execute frequency DISPLAY HERE IS REG0 $0 DISPLAY HERE IS REGF $F goto 3 To UNSUBSCRIBE from techtoolslist, send a message with "UNSUBSCRIBE" in the message body to: techtoolslist-request@flippers.com. Please direct other questions, comments, or problems to jrr@flippers.com.