Im making a multipurpose board of the Philips P89v51 , I had the following doubts...
1) Do i connect pullup resistors only to the PORT0 or to all the ports... a book i read recently tells me that PORTS1,2,and3 have inbuilt resistors.
A doubt about the L293D
2) What will happen if I connect the 12V point in the L293D chip, to a 5V source? Will the motors run slowly?