hi, i am very new to programming. i am using 89v51rd2. i want to write a programm for port 1 as input and port 2 as output. port 1 is externally pulled high. when p1.0 goes low, p2.0 should be high. but i am not able to make p2.0 high. ULN 2803 is interfaced to port 2. i am writting programm in C language. when ULN is not inserted in CKT port 2 remains high, but when ULN is inserted its voltage drops to 0.33 volt. Can any body tell mesolution for program.