Visible to Intel only — GUID: vsr1678680363604
Ixiasoft
6.7. Custom Instructions
Nios® V/g and Nios® II/f processors support custom instruction.
Feature | Nios® V/g Processor | Nios® II/f Processor |
---|---|---|
Supported custom instruction types |
|
|
Combinational instructions | Implemented in two cycles. | Implemented in a single cycle. |
Multicycle instructions | Supports variable length multicycle instructions. | Supports fixed length and variable length multicycle instructions. |
Extended instructions | Apply the signal ctrl[31:0] to select the appropriate instruction. | Apply the signal n[7:0] to select the appropriate instruction. |
Internal Register Files instructions | Not Supported | Supported |
Manager Interface | Nios® V Processor Custom Instruction Manager | Nios® II Processor Custom Instruction Manager |
Agent Interface | Nios® V Processor Custom Instruction Subordinate | Nios® II Processor Custom Instruction Subordinate |
Signals and Interface |
|
|
Built-in functions (To use non-integer types with instructions) | Not supported | Supported |
FPH2 Hardware | Replaced with internal FPU | Supported |
5 alu_result is not equivalent to clk_en.
6 Nios® V Processor Custom Instruction does not support clk_en signal.