Z80Next instructions opcodes The Z80 on the Next has extra instructions that are unique to it. Below is a table of the opcode bytes that are required to select those instructions. The timings are based on some partial testing. These may not be accurate. Also there's initiative led by Matt Davies (author of Odin assembler/editor/debugger tool for ZX Next) to have 4-letter aliases for all new instructions using long mnemonics, the abbreviations suggested are in the last column of the table. Instruction 4-char mnemomic Byte1 Byte2 Byte3 Byte4 TStates SWAPNIB SWAP ED 23 8 MIRROR A MIRR ED 24 8 TEST $im8 TEST $im8 ED 27 value 11 BSLA DE,B BSLA DE,B ED 28 8 BSRA DE,B BSRA DE,B ED 29 8 BSRL DE,B BSRL DE,B ED 2A 8 BSRF DE,B BSRF DE,B ED 2B 8 BRLC DE,B BRLC DE,B ED 2C 8 MUL D,E MUL D,E ED 30 8 ADD HL,A ADD HL,A ED 31 8 ADD DE,A ADD DE,A ED 32 8 ADD BC,A ADD BC,A ED 33 8 ADD HL,$im16 ADD HL,$im16 ED 34 low high 16 ADD DE,$im16 ADD DE,$im16 ED 35 low high 16 ADD BC,$im16 ADD BC,$im16 ED 36 low high 16 PUSH $im16 PUSH $im16 ED 8A high low 23 OUTINB OTIB ED 90 16 NEXTREG $im8,$im8 NREG $im8,$im8 ED 91 reg value 20 NEXTREG $im8,A NREG $im8,A ED 92 reg 17 PIXELDN PXDN ED 93 8 PIXELAD PXAD ED 94 8 SETAE STAE ED 95 8 JP (C) JP (BC) ED 98 13 LDIX LDIX ED A4 16 LDWS LDWS ED A5 14 LDDX LDDX ED AC 16 LDIRX LIRX ED B4 21/16 LDPIRX LPRX ED B7 21/16 LDDRX LDRX ED BC 21/16 Note that the "PUSH $im16" instruction is not a mistake. The operand is encoded big-endian.