Two comments in the native assembler survived the changes that made them
false, and both are the kind that misleads rather than merely ages.
Asm.asm still explained an eighteen kilobyte buffer that the whole output
had to fit in "because a file is written in one call and there is nowhere
to put half of one" - which stopped being true when the assembler learned
to stream, and the variable it described, ImgRoom, does not exist any more.
It was sitting in front of the comment that replaced it, so the paragraph a
reader met first described the design that had been taken out. Replaced by
what is actually there: no limit but the disk, one block at a time through
a window in scratch.
scratch.asm said the system keeps below 0x1000 twelve lines above the
paragraph explaining that the system's half of Data Memory was doubled to
0x1FFF. A stale number next to its own correction is worse than a stale
number alone, because which one a reader believes is a coin toss.
docs.sh now checks both of the facts scratch.asm asserts about the machine
around it: the floor it claims the system keeps below, against the CosmOS
README, and the address its buffers start at, against where the assembler's
own data actually ends. Neither is enforced by a line of code anywhere -
the map is a comment, deliberately, because reserving the buffers would put
22K of zeroes in the file and the assembler could not load itself - so a
check is the only thing that can hold them. Both fail when broken; the
second reports the exact overlap.
Anachronaut
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