stardot / b-em

An opensource BBC Micro emulator for Win32 and Linux
http://stardot.org.uk/forums/viewtopic.php?f=4&t=10823
GNU General Public License v2.0
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CiscOS memory map changes #213

Closed rjpontefract closed 8 months ago

rjpontefract commented 8 months ago

CiscOS determines the amount of memory available by writing a known value to 0x00000000 and then checking every 1K (0x400) bytes for that value. The original hardware presumably only decoded the address lines it needed for the installed memory causing the memory to be available at every multiple of the RAM size.