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8-bit acorn emulators • Re: Importing external binary data into BeebEm

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The BBC doesn't really have the concept of file type. A file has attributes (which can be ignored):
  • Load address. This is the default location in memory where a file would be placed with *LOAD or *RUN. *LOAD can override this default value.
  • Exec address. This is the default address where a program is run. It only really makes sense for machine code and is used by *RUN.
  • Lock flag. This makes the file readonly.
BASIC typically does set load and exec addresses (eg FFFF1900, FFFF8023) but it ignores them when LOADing.

So, for example:

Code:

% beeb info Games.ssd Disk title: Games (23)  Disk size: &320 - 200KBoot Option: 3 (EXEC)   File count: 10Filename:  Lck Lo.add Ex.add Length Sct$.CYLON        001900 008023 001E21 0DAA.CYLON        002000 006909 004A00 090$.CHUCKIE      001100 0029AB 002700 069$.MENU         FF1900 FF8023 000A52 05E$.!BOOT        00FFFF 00FFFF 000011 05D$.ZALAGA       001900 00801F 0000B5 05CA.ZALAGA       002582 002582 000400 058B.ZALAGA       003000 004522 002D25 02A$.DARE         001900 00801F 0000AE 029A.DARE         004000 006691 002700 002
The file "A.CYLON" can be *RUN and loads at 002000 and executes at 006909

A datafile doesn't really have meaningful load/exec addresses.

Statistics: Posted by sweh — Sat Nov 09, 2024 1:16 am



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