[futurebasic] Please consider this revision

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From: Bill Kuck <wmkuck@...>
Date: Sat, 16 Dec 2000 00:34:59 -0800
Ref:   exprA NAND exprB
       expr NOR exprB

Please consider revising the boolean operations for NAND and NOR to agree
with the NAND and NOR operations consistent with digital logic texts.
FB^3 is calculating;   exprA AND NOT exprB for the NAND operation and,
                       exprA OR NOT exprB for the NOR operation

Normally, two expressions to be NAND'd or NOR'd are considered:
NOT (exprA AND exprB) for the NAND operation and,
NOT (exprA OR exprB) for the NOR operation

I have included an example below to illustrate these results.  Look at the
individual bit patterns and you will see what I mean...

A value          00000000 00000000 00000000 00110101
B value          00000000 00000000 00000000 00101111
A NAND B         00000000 00000000 00000000 00010000 <-- FB^3 answer
A NAND B         00000000 00000000 00000000 00011010 <-- correct answer

A value          00000000 00000000 00000000 00110101
B value          00000000 00000000 00000000 00101111
A NOR B          11111111 11111111 11111111 11110101 <-- FB^3 answer
A NOR B          11111111 11111111 11111111 11000000 <-- correct answer

All other boolean logic operations are working fine.  The truth tables in
the manuals for NAND and NOR would need to be changed too.

A value          00000000 00000000 00000000 00110101
B value          00000000 00000000 00000000 00101111
A AND B          00000000 00000000 00000000 00100101 <-- FB^3 correct
----------------------------------------------------
A value          00000000 00000000 00000000 00110101
B value          00000000 00000000 00000000 00101111
A OR B           00000000 00000000 00000000 00111111 <-- FB^3 correct
----------------------------------------------------
A value          00000000 00000000 00000000 00110101
NOT A            11111111 11111111 11111111 11001010 <-- FB^3 correct
----------------------------------------------------
A value          00000000 00000000 00000000 00110101
B value          00000000 00000000 00000000 00101111
A XOR B          00000000 00000000 00000000 00011010 <-- FB^3 correct