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  • Re: Why $0401, $0801, $1c01? Why not $0400,

    From nospam.K-Guide@nospam.K-Guide@f230.n130.z1.fidonet.org (K-Guide) to All on Sunday, February 14, 2021 08:10:06
    From Newsgroup: comp.sys.cbm

    On Fri 12-Feb-2021 7:27a, Pzembrod@gmail.com@3:770/3.0 wrote:
    I figure that someone here probably knows why CBM's basic RAM always
    started at $xx01 addresses, like $0801, $0401, $1001, $1c01 instead of $0800, $0400, $1000, $1c00?

    What is sitting in that one byte, or what role is it playing?

    I am not sure about the other systems, but on the C64 the Byte at $800 indicates your intention to use the following bank for Basic. If you store anything other that 0 in that Byte, then Basic programs will not run.

    [+] K-Guide
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