Query on ALE pin of 8051.

From: Aliasger (aliasger_18_at_hotmail.com)
Date: 04/26/04 

Date: 26 Apr 2004 02:14:38 -0700

hi

i was working on a circuit based on an 8051 microcontroller. 89C52 to
be precise. till date my program wasn't executing at all. the program
counter wasn't moving ahead. i had connected the ALE pin (pin 30) to
ground and after floating it, the circuit was running fine.

ALE is a output active high pin and i wasn't aware that it shouldn't
be forcefully grounded. i'm still not sure why you shouldn't tie
output pins to vcc or ground. is there some logic behind this?

thanks

ali

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