| 転送命令系 | LD | Load |
| LD@ | Load Indirect |
| LI | Load Immediate |
| LSEX | Load with sign extended |
| ST | Store |
| ST@ | Store Indirect |
| RCPY | Register Copy |
| RXCH | Register Exchange |
| XCHRS | Exchange Register and Stack |
| CFR | Copy Flags into Register |
| CRF | Copy Register into Flags |
| PUSH | Push Register onto Stack |
| PUSHF | Push Flags onto Stack |
| PULL | Pull Stack into Register |
| PULLF | Pull Stack into Flags |
| 演算命令系 | ADD | Add |
| RADD | Register Add |
| RADC | Register Add with Carry |
| DECA | Decimal Add |
| SUBB | Substruct with Borrow |
| AND | AND |
| RAND | Register AND |
| OR | OR |
| RXOR | Register XOR |
| CAI | Complement with Add Immediate |
| SHL | Shift Left |
| SHR | Shift Right |
| ROL | Rotate Left |
| ROR | Rotate Right |
| ジャンプ命令系 | JMP | Jump |
| JMP@ | Jump Indirect |
| BOC | Branch On Condition |
| SKNE | Skip if not Equal |
| SKG | Skip if Greater |
| SKAZ | Skip if And is Zero |
| ISZ | Increment and Skip if Zero |
| DSZ | Decrement and Skip if Zero |
| AISZ | Add Immediate and Skip if Zero |
| JSR | Jump to Subroutine |
| JSR@ | Jump to Subroutine Indirect |
| RTS | Return from Subroutine |
| RTI | Return from Intrrupt |
| その他 | HALT | Halt |
| SFLG | Set Flag |
| PFLG | Pulse Flag |
右は INS8900のチップ写真。