Improves the Atari ST:

• the emulator's high-level implementation of the IntelligentKeyboard protocol now supports absolute mouse positioning and inverted scales;
  • known fixed titles: Lemmings, Gridrunner;
• I've made a new guess at the mechanism behind the vertical/horizontal interrupts, preventing multiple firings;
  • known fixed titles: Cisco Heat, E-Motion; and
• a potential buffer overrun in the emulated graphics subsystem has been fixed.

Also continues the whipping of my 68000 into shape, currently to benefit the Atari ST and the Macintosh:

• further CHK fixes:
  • N is now set correctly where the destination value is both < 0 and greater than the effective address;
  • a previously missing prefetch cycle has been added to the (xxx).l/w, d(An/PC) and d(An/PC, Xn) address modes; and
• the processor no longer returns to a STOP it was already at after an interrupt.