mem: reserve top 4 physical pages for the NMI break monitor#147
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Signed-off-by: Matthias Brukner <mbrukner@gmail.com>
Signed-off-by: Matthias Brukner <mbrukner@gmail.com>
Signed-off-by: Matthias Brukner <mbrukner@gmail.com>
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Reserve physical memory pages
$3c-$3f(the top 4 × 8KB banks) for a 2-bank NMI break monitor — two banks for screen save and two for the monitor code.Lowers
MaxPhysPagefrom 64 to 59 inmemory.asm, so the dynamic program-data page allocator stops before those reserved banks. This is groundwork for the break monitor; it reduces available program memory by 5 pages (40KB).Verified the build still assembles with no overflow.