Quote Originally Posted by Bruce View Post
....... The faster the core is running, and the more external capacitance there is, the more you will have problems with read-modify-write. ....
Thank you Skimask, Bruce, Pic_user and all other for your support.

The more one comes familiar with PIC, there are more and more that is not advertised by Microchip in the first place, mais c'est la vie....

Before this problem, I was not aware of such a thing as r-m-w. Now I think I understand what the phenomena is. In a matter of fact, I was kind of lucky when I run into this TOGGLE problem.

Thank you once again for your kind help....

Regards
Key