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

33.6.1.1. Adding the EIC Interface Shadow Register Set

This section describes how to add the EIC interface and shadow register sets to a Nios® II processor core in Platform Designer, through the parameter editor interface.

  1. In Platform Designer, double-click the Nios® II processor to open the parameter editor interface.
  2. Enable the EIC interface on the Nios® II processor by selecting it in the Interrupt Controller list in the Advanced Features tab, as shown in the figure below.

    There are two options for Interrupt Controller: Internal and External. If you select Internal, the processor is implemented with the internal interrupt controller. Select External to implement the processor with an EIC interface.

    Note: When you implement the EIC interface, you must connect an EIC, such as the VIC. Failure to connect an EIC results in a Platform Designer error.
  3. Select the desired number of shadow register sets. In the Number of shadow register sets list, select the number of register sets that matches your system performance goals.
  4. Click Finish to exit from the Nios® II parameter editor interface . Notice that the processor shows an unconnected interrupt_controller_in Avalon® -ST sink, as shown in the figure below.
Figure 139. Configuring the Interrupt Controller and Shadow Register Sets
Figure 140.  Nios® II Processor with EIC Interface

Shadow register sets reduce the context switching overhead associated with saving and restoring registers, which can otherwise be significant. If possible, add one shadow register set for each interrupt that requires high performance.