Hi
I am using 89V51RD2 developed by Philips. I use Keil C51 to program it and Flash magic to burn the program.
Everything works fine but when I use Port 2, it is not giving output as expected.
Only for
P2=0xff
or
P2=0x88
the port 2 is activated and for all other inputs such as
P2=0x01
etc. no pin is pulled up. What could be wrong? Is my program wrong?
anything connected externally? salvaged chip? will the pins pull up with an external resistor?
Erik
I didnt connect anything externally. The chip is not damaged as it shows +5V when
P2=0XFF
is programmed. How to pull up using external resistor?
as it shows +5V when P2=0XFF
if 'it' is P2 then your first post makes no sense
show a complete test program for this