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

27.2.3. Addressing and Address Incrementing

When accessing memory, the read (or write) address increments by 1, 2, 4, 8, or 16 after each access, depending on the width of the data. On the other hand, a typical peripheral device (such as UART) has fixed register locations. In this case, the read/write address is held constant throughout the DMA transaction.

The rules for address incrementing are, in order of priority:

  • If the control register’s RCON (or WCON) bit is set, the read (or write) increment value is 0.
  • Otherwise, the read and write increment values are set according to the transfer size specified in the control register, as shown below.
    Table 312.  Address Increment Values
    Transfer Width Increment
    byte 1
    halfword 2
    word 4
    doubleword 8
    quadword 16

    In systems with heterogeneous data widths, care must be taken to present the correct address or offset when configuring the DMA to access native-aligned agents. For example, in a system using a 32-bit Nios® II processor and a 16-bit DMA, the base address for the UART txdata register must be divided by the dma_data_width/cpu_data_width—2 in this example.