Changes
Z80
,/* Letter R */
| ret C || 11ccc000 || 4/2 || 11/5 (5,3,3/5)|| - || - || - || - || - || - || - || - || if C then pc := (sp), sp += 2 || Conditional Return
|-
| reti || 11101101 01**1101 01001101 || 4 || 14 (4,4,3,3) || - || - || - || - || - || - || - || - || pc := (sp), sp += 2, iff1 := iff2 || Return from Interrupt
|-
| retn || 11101101 01**0101 *101 || 4 || 14 (4,4,3,3) || - || - || - || - || - || - || - || - || pc := (sp), sp += 2, iff1 := iff2 || Return from NMI
|-
| rla || 00010111 || 1 || 4 (4) || - || - || + || 0 || + || - || 0 || X || ocf := cf, cf := a.7, a := [a << 1] + ocf || Rotate Left Accumulator
