On Wed, 26 Nov 1997 09:50:33 -0500 myke predko writes: >>movlw 0x0F8 >>andwf STATUS >The purpose of this was to clear the Zero, Half Carry and Carry >Flags in the Status Register so changes caused by different >instrutions could be easily seen. It doesn't work this way though. Since the andwf instruction inherently affects the Z flag, the PIC logic will 'lock out' the write to the other 2 flags. The result: Z - Set if high 5 bits of STATUS = 00000, clear otherwise. C - Unchanged. DC - Unchanged. I suggest using either 3 bcf instructions or movlw 0 / movwf STATUS to clear the flags. This also clears the page select bits of course. Notice that clrf STATUS will not work for the same reason andwf STATUS doesn't. However, movwf doesn't inherently affect any status bits so it will write to the bits properly.