If you read the "bible" or some other document describing the port structure of 8051 or derivatives you will find that it is not recommended to set the port LO and try to pull it HI buy some external signal. That is because of the internal structure of the port. If you want to do the other way, fine, but don't ask for advise, get advise from members of the forum and then ignore what is written by people who has worked with this type of micros for many years. There is always a reason (or many) for a standard way of doing things and you should not change that without a very good reason. (A not so good HW design can be changed.) My advise is: download a simulator and START USING IT and follow the advise given to you several times by other members; don't post a code snippet and ask what is wrong with it. You can check the timing in the delayloops very easy in a simulator and also test with "ideal" inpulses to see what happens with registers when you feed the pulses to the port.

Regards
Anders