Nios® V Processor Software Developer Handbook

ID 743810
Date 7/08/2024
Public
Document Table of Contents

9.4. Nios® V Processor Timer Interrupt Service Routine

The Nios® V processor timer interrupt service routine manages the internal timer based on the RISC-V specification. The following registers represent the main components of the internal timer.

  • mtime – Real-time counter which increments at a constant frequency.
  • mtimecmp – Timer compares register for interrupt generation.

The processor timer ISR is essential for the critical timing routine within the processor operating system. Thus, Altera does not recommends for user-level applications. Alternatively, refer to Developing Programs Using the Hardware Abstraction Layer – Using Timer Devices for more information on developing user-level application using system clock, alarm, and timestamp.