>Maybe I'm old and I missed it but I have been lurking for the last few days
>and I don't believe I saw anyone drop the magical reference "A" to the
>discussion on the 16C74 protection bits.

My experience was with an "A" part.  The '76/'77 (no "A") both feature the
difficult-to-erase fuse.

>A good rule of thumb to remember:

Rules are made to be broken, as evidenced by the 12C parts. <G>

Andy

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Andy Kunz - Montana Design - 409 S 6th St - Phillipsburg, NJ 08865
          Hardware & Software for Industry & R/C Hobbies
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