> How would I calculate how long 1 nop takes ?' 1 NOP takes one instruction cycle. For a 16F PIC, if it's running at 4MHz for example, divide that by 4 to get the actual processing speed, which is therefore 1MHz = 1us per instruction cycle Fosc and instruction execution times are covered in the datasheet -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist