The J-type (jump) instruction is similar to the U-type instruction but differs only in the way the immediate field is arranged. Figure 1 describes how the J-type instruction format is divided into its respective fields.
Figure 1: Instruction Format
- Opcode: The opcode or operation code is a
7-bitfield that defines the type of operation to be performed. - Destination Register: Stores the result of the operation in the destination register
rd. - Immediate Field: A
20-bitimmediate value is the difference of the label address andjaladdress such that the addition of thejalanddiffis equal to label address.
Note: The ordinary j jump instruction is encoded as jal where rd is set to zero.
Below is table that describes the list of U-type instructions.
| opcode | Description | Instruction |
|---|---|---|
| 1101111 (111) | jump and link | jal rd, label |