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Question about section 5.4 ... 0 in bit 5 means uppercase?

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Question about section 5.4 ... 0 in bit 5 means uppercase?

Costello, Roger L.
Hi Folks,

In section 5.4 Chunk Naming Conventions it says:

        Four bits of the chunk type, the property bits, namely
        bit 5 (value 32) of each byte, are used to convey chunk
        properties. This choice means that a human can read
        off the assigned properties according to whether the
  letter corresponding to each byte of the chunk type is
  uppercase (bit 5 is 0) or lowercase (bit 5 is 1).

I think the second sentence is saying (or implying) that every uppercase ASCII letter has 0 in bit 5. But that is not true; for example, E is hex 45 (0100 0101), which means it has 1 in bit 5.

Either I am misunderstanding the second sentence (most likely) or it is a false statement.

Please advise.

/Roger



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Re: Question about section 5.4 ... 0 in bit 5 means uppercase?

Glenn Randers-Pehrson
Bits are numbered 0..7 from the right, so E == hex 45 == 0100 0101 has a 0 in bit 5 (and e == hex 65 == 0110 0101 has a 1).

On Fri, Jul 1, 2016 at 1:44 PM, Costello, Roger L. <[hidden email]> wrote:
Hi Folks,

In section 5.4 Chunk Naming Conventions it says:

        Four bits of the chunk type, the property bits, namely
        bit 5 (value 32) of each byte, are used to convey chunk
        properties. This choice means that a human can read
        off the assigned properties according to whether the
        letter corresponding to each byte of the chunk type is
        uppercase (bit 5 is 0) or lowercase (bit 5 is 1).

I think the second sentence is saying (or implying) that every uppercase ASCII letter has 0 in bit 5. But that is not true; for example, E is hex 45 (0100 0101), which means it has 1 in bit 5.

Either I am misunderstanding the second sentence (most likely) or it is a false statement.

Please advise.

/Roger




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