Hi Peter:

I appreciate your comment because I made a lot of mistakes. But not this time.
Could you please tell me where I said that MOV C, P1.7 is a read-modify-write instruction ?
If you read carefully my post I said that CPL C is one way to do what Jeff asked, but as the original post used a read-modify-write instruction ( MOV PX.Y, C ) I considered opportune to mention this subject and offer another option.
That's all.

Good Luck
Daniel