Changes
Z80
,/* Z80 Instructions */
| e || 16-bit relative address || dddddddd (e minus address of next instruction)
|-
| ixy || Index register (ix, iy) || i b = 0, 1
|-
| p || Half index register (ixh, ixl, iyh, iyl) || (i, b) = (0, 0), (0, 1), (1, 0), (1, 1)
