Prakash, nothing personal, just using this as a base for this 'editorial'
Here, again we are in a lenghty discussion about something that should not be a problem. With ISP chips being the norm for any new non-OTP design, why is Prakash screwing around with a "programmer by Asim Khan". So much valuable time is wasted trying to make programmers work, and when the chip is programmed, you do not have any idea of the data retention (was the flash capacitor charged just enough or fully).
Then when Prakash has got the programmer to work, he comes back with questions on the 8255 and - again - we are discussing problems that are generated by using an obsolete process.

Why can new designs not be new?

Erik