Hi all,

I've wrote the follwing code :

#include <reg51.h>
main ()
{
AUXR = 0;
while(1)
{
P1=0;
P1=255;
}
}

in order to see if my hardware works correctly.
This program should make ALE output inactive, the Address bus inactive and the P1 port should have a square signal on its pins.
Then, I sends the hex file with FlashMagic and I can check by display the memory that my 50 octets are written correctly at the 0000h beggining address.
So I change from PSEN=0 and EA=5V to PSEN=5V and EA=0V and .....
... nothing happens !
The ALE output is still active, the Adress bus is still active and nothing on the P1 ports
Is there something missing in my software initialization to make my software working or may it be an hardware problem ?
Any idea ?
Thanks

Stephane