Instruction set of 3niti alpha has 3 groups of commands:

• load register A from other register (opcode starts with P) - LAr (where r is a name of any directly available register used as source);
• save register A to other register (opcode starts with N) - SAr (where r is a name of any directly available register used as destination);
• and other commands (opcode starts with O).

Full instruction set:

• NNN (-13) SAN - save value from register A to register N (memory cell with address DPn);
• NNO (-12) SAO - save value from register A to register O (memory cell with address DPo);
• NNP (-11) SAP - save value from register A to register P (memory cell with address DPp);
• NON (-10) SAF - save value from register A to register F;
• NOO (-9) SPCD - save value from PC (program counter) to current DP (data pointer);
• NOP (-8) SAB - save value from register A to register B;
• NPN (-7) SAL - save value from register A to register L (lower triad of current data pointer);
• NPO (-6) SAM - save value from register A to register M (middle triad of current data pointer);
• NPP (-5) SAH - save value from register A to register H (higher triad of current data pointer);
• ONN (-4) RLA - rotate register A to the left through flag BCF;
• ONO (-3) ADD - add register A with B and flag BCF, save result to A and BCF, modify sign flag RSF;
• ONP (-2) RRA - rotate register A to the right through flag BCF;
• OON (-1) LAI # - load register A from immediate triad;
• OOO (0) ADI # - add register A with immediate triad and flag BCF, save result to A and BCF, modify sign flag RSF;
• OOP (1) OPA # - perform unary "tritwise" operation over register A (function is defined by immediate triad), modify sign flag RSF;
• OPN (2) LDI # # # - load current DP (data pointer) by immediate 3 triads (higher triad, middle triad, lower triad);
• OPO (3) JMP # # # - jump to address (copy to PC) set by immediate 3 triads (higher triad, middle triad, lower triad);
• OPP (4) OPB # # # - perform binary "tritwise" operation over registers A and B, save result to A (function is defined by immediate 3 triads), modify sign flag RSF;
• PNN (5) LAN - load register A by value from register N (memory cell with address DPn);
• PNO (6) LAO - load register A by value from register O (memory cell with address DPo);
• PNP (7) LAP - load register A by value from register P (memory cell with address DPp);
• PON (8) LAF - load register A by value from register F;
• POO (9) LPCD - load PC (program counter) by value from current DP (data pointer);
• POP (10) LAB - load register A by value from register B;
• PPN (11) LAL - load register A by value from register L (lower triad of current data pointer);
• PPO (12) LAM - load register A by value from register M (middle triad of current data pointer);
• PPP (13) LAH - load register A by value from register H (higher triad of current data pointer).