Changes
/* Technical */
NOTE: It seems the RAM can only be accessed after the red button has been pressed.
The ROM is made visible by pressing the red button which causes an [[NMI ]] and execution starts at 0066. The ROM is visible at 0000-1fff with a mirror at 2000-ffff. The ROM overrides the internal CPC OS ROM and also disables the RAM where it is mapped (i.e. RAM in the range 0000-3fff is disabled). Therefore writing to RAM under the ROM is not possible.
The ROM state is also toggled by reading an opcode from an address >0x03000 and less than <0x03fff. The ROM itself uses 3FFB which contains a RET
