Re: Blank CMS SCSI Card PCBs

[r_beaudry@hotmail.com (Rich Beaudry)]

mjmahon@aol.com (Michael J. Mahon) wrote in message news:<20020425160322.02376.00004988@mb-fc.aol.com>...
> Rich Beaudry asked:
> 
> >- Would reading a PAL with the security bit set damage the PAL?
> 
> No.  In this case "reading" means merely determining the inputs
> and outputs and finding the truth table by applying all combinations
> of inputs and reading all outputs.  This is a simple "behavioral" test
> which is no more than what the PAL does in normal operation.
> 

I understand what you're saying, Michael, but think of this... If it
truly didn't hurt tht PAL, then why have the bit?  Any PROM programmer
hardware could simply try all combinations, store the values, and burn
another, right??

I guess I've answered my own question ... Sort of ... Unless the
security bit doesn't prevent reading, but somehow obfuscates the
output??

I guess I need to do some research, and find out what happens...

Michael, you might not want to build that circuit until we can
determine if damage will be caused...

Rich B.