AN 977: Nios® V Processor Custom Instruction

ID 773194
Date 4/14/2023
Document Table of Contents

2.2. Multicycle Custom Instructions

Multicycle (sequential) custom instructions consist of a logic block that requires two or more clock cycles to complete an operation. Multicycle custom instructions complete in variable number of clock cycles. Thus, you need to instantiate the enable and done ports. The enable and done ports participate in a handshaking scheme to determine when the custom instruction execution completes.