Embedded Peripherals IP User Guide

ID 683130
Date 10/24/2025
Public
Document Table of Contents
1. Introduction 2. Avalon® -ST Serial Peripheral Interface Core 3. SPI Core 4. SPI Agent/JTAG to Avalon® Host Bridge Cores 5. Intel eSPI Agent Core 6. eSPI to LPC Bridge Core 7. Ethernet MDIO Core 8. Intel FPGA 16550 Compatible UART Core 9. UART Core 10. Lightweight UART Core 11. JTAG UART Core 12. Intel FPGA Avalon® Mailbox Core 13. Intel FPGA Avalon® Mutex Core 14. Intel FPGA Avalon® I2C (Host) Core 15. Intel FPGA I2C Agent to Avalon® -MM Host Bridge Core 16. EPCS/EPCQA Serial Flash Controller Core 17. Intel FPGA Serial Flash Controller Core 18. Intel FPGA Serial Flash Controller II Core 19. Intel FPGA Generic QUAD SPI Controller Core 20. Intel FPGA Generic QUAD SPI Controller II Core 21. Interval Timer Core 22. Intel FPGA Avalon FIFO Memory Core 23. On-Chip Memory (RAM and ROM) Intel FPGA IP 24. On-Chip Memory II (RAM or ROM) Intel FPGA IP 25. PIO Core 26. PLL Cores 27. DMA Controller Core 28. Modular Scatter-Gather DMA Core 29. Scatter-Gather DMA Controller Core 30. Video Sync Generator and Pixel Converter Cores 31. Intel FPGA Interrupt Latency Counter Core 32. Performance Counter Unit Core 33. Vectored Interrupt Controller Core 34. System ID Peripheral Core 35. Intel FPGA GMII to RGMII Converter Core 36. HPS GMII to RGMII Adapter IP 37. Intel FPGA MII to RMII Converter Core 38. HPS GMII to TSE 1000BASE-X/SGMII PCS Bridge Core IP 39. Intel FPGA HPS EMAC to Multi-rate PHY GMII Adapter Core 40. Intel FPGA MSI to GIC Generator Core 41. Cache Coherency Translator IP 42. Altera ACE5-Lite Cache Coherency Translator

33.1. Core Overview

The ability to process interrupt events quickly and to handle large numbers of interrupts can be critical to many embedded systems. The Vectored Interrupt Controller (VIC) is designed to address these requirements. The VIC can provide interrupt performance four to five times better than the Nios® II processor’s default internal interrupt controller (IIC). The VIC also allows expansion to a virtually unlimited number of interrupts, through daisy chaining.

The vectored interrupt controller (VIC) core serves the following main purposes:

  • Provides an interface to the interrupts in your system
  • Reduces interrupt overhead
  • Manages large numbers of interrupts

    The VIC offers high-performance, low-latency interrupt handling. The VIC prioritizes interrupts in hardware and outputs information about the highest-priority pending interrupt. When external interrupts occur in a system containing a VIC, the VIC determines the highest priority interrupt, determines the source that is requesting service, computes the requested handler address (RHA), and provides information, including the RHA, to the processor.

The VIC core contains the following interfaces:

  • Up to 32 interrupt input ports per VIC core
  • One Avalon® Memory-Mapped ( Avalon® -MM) agent interface to access the internal control status registers (CSR)
  • One Avalon® Streaming ( Avalon® -ST) interface output interface to pass information about the selected interrupt
  • One optional Avalon® -ST interface input interface to receive the Avalon® -ST output in systems with daisy-chained VICs

    The Sample System Layout Figure below outlines the basic layout of a system containing two VIC components.

Figure 136. Sample System Layout

The VIC core provides the following features:

To use the VIC, the processor in your system needs to have a matching Avalon® -ST interface to accept the interrupt information, such as the Nios® II processor's external interrupt controller interface.

The characteristics of each interrupt port are configured via the Avalon® -MM agent interface. When you need more than 32 interrupt ports, you can daisy chain multiple VICs together.

  • Separate programmable requested interrupt level (RIL) for each interrupt
  • Separate programmable requested register set (RRS) for each interrupt, to tell the interrupt handler which processor register set to use
  • Separate programmable requested non-maskable interrupt (RNMI) flag for each interrupt, to control whether each interrupt is maskable or non-maskable
  • Software-controlled priority arbitration scheme

    The VIC core is Platform Designer ready and integrates easily into any Platform Designer generated system. For the Nios® II processor, Intel provides Hardware Abstraction Layer (HAL) driver routines for the VIC core. Refer to to Intel FPGA HAL Software Programming Model section for HAL support details.