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# I-type
## I-Format Instruction Layout
* The `funct7` and `rs2` fields from R-format are replaced by 12-bit signed immediate, `imm[11:0]` (in range \[-2048, 2047]).
* Remaining fields (`rs1`, `funct3`, `rd`, `opcode`) same as R-format.
* Immediate is always sign-extended to 32-bits before use in an arithmetic operation.
### I-immediate
Immediate generator generates I-type immediate
## I-Format Arithmetic Instructions
I-Format Arithmetic Instructions
### Adding I-Format arithmetic instructions to datapath
## I-Format Load Instructions
Load instructions are also I-type.
Load Instruction Layout
* Reg\[rd] <- Mem\[Reg\[rs1] + offset]
* The 12-bit immediate is added to the base address in `rs1` to form the memory address
* The value loaded from memory is stored in register `rd`
I-Format Load Instructions
{% hint style="info" %}
Note that the `funct3` field is to specify the width (i.e., the amount of bytes) and signedness of load data.
{% endhint %}
### Adding load instructions to datapath