Embedded Peripherals IP User Guide

ID 683130
Date 8/11/2025
Public
Document Table of Contents
1. Introduction 2. Avalon® -ST Single-Clock and Dual-Clock FIFO Cores 3. Avalon® -ST Serial Peripheral Interface Core 4. SPI Core 5. SPI Agent/JTAG to Avalon® Host Bridge Cores 6. Intel eSPI Agent Core 7. eSPI to LPC Bridge Core 8. Ethernet MDIO Core 9. Intel FPGA 16550 Compatible UART Core 10. 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. Intel FPGA Avalon® Compact Flash Core 17. EPCS/EPCQA Serial Flash Controller Core 18. Intel FPGA Serial Flash Controller Core 19. Intel FPGA Serial Flash Controller II Core 20. Intel FPGA Generic QUAD SPI Controller Core 21. Intel FPGA Generic QUAD SPI Controller II Core 22. Interval Timer Core 23. Intel FPGA Avalon FIFO Memory Core 24. On-Chip Memory (RAM and ROM) Intel FPGA IP 25. On-Chip Memory II (RAM or ROM) Intel FPGA IP 26. Optrex 16207 LCD Controller Core 27. PIO Core 28. PLL Cores 29. DMA Controller Core 30. Modular Scatter-Gather DMA Core 31. Scatter-Gather DMA Controller Core 32. SDRAM Controller Core 33. Tri-State SDRAM Core 34. Video Sync Generator and Pixel Converter Cores 35. Intel FPGA Interrupt Latency Counter Core 36. Performance Counter Unit Core 37. Vectored Interrupt Controller Core 38. Avalon® -ST Data Pattern Generator and Checker Cores 39. Avalon® -ST Test Pattern Generator and Checker Cores 40. System ID Peripheral Core 41. Avalon® Packets to Transactions Converter Core 42. Avalon® -ST Multiplexer and Demultiplexer Cores 43. Avalon® -ST Bytes to Packets and Packets to Bytes Converter IP 44. Avalon® -ST Delay Core 45. Avalon® -ST Round Robin Scheduler Core 46. Avalon® -ST Splitter Core 47. Avalon® -MM DDR Memory Half Rate Bridge Core 48. Intel FPGA GMII to RGMII Converter Core 49. HPS GMII to RGMII Adapter Intel® FPGA IP 50. Intel FPGA MII to RMII Converter Core 51. HPS GMII to TSE 1000BASE-X/SGMII PCS Bridge Core Intel® FPGA IP 52. Intel FPGA HPS EMAC to Multi-rate PHY GMII Adapter Core 53. Intel FPGA MSI to GIC Generator Core 54. Cache Coherency Translator Intel® FPGA IP 55. Altera ACE5-Lite Cache Coherency Translator 56. Lightweight UART Core

47.1. Core Overview

The Avalon® Memory-Mapped (MM) Half-Rate Bridge core is a special-purpose clock-crossing bridge intended for CPUs that require low-latency access to high-speed memory. The core works under the assumption that the memory clock is twice the frequency of the CPU clock, with zero phase shift between the two. It allows high speed memory to run at full rate while providing low-latency interface for a CPU to access it by using lightweight logic that translates one single-word request into a two-word burst to a memory running at twice the clock frequency and half the width. For systems with a 8-bit DDR interface, using the Half-Rate DDR Bridge in conjunction with a DDR SDRAM high-performance memory controller creates a datapath that matches the throughput of the DDR memory to the CPU. This half-rate bridge provides the same functionality as the clock crossing bridge, but with significantly lower latency—2 cycles instead of 12.

The core’s host interface is designed to be connected to a high-speed DDR SDRAM controller and thus only supports bursting. Because the agent interface is designed to receive single-word requests, it does not support bursting. The figure below shows a system including an 8-bit DDR memory, a high-performance memory controller, the Half-Rate DDR Bridge, and a CPU.

Figure 159.  Platform Designer Memory System Using a DDR Memory Half-Rate Bridge

The Avalon® -MM DDR Memory Half-Rate Bridge core has the following features and requirements:

  • Platform Designer ready with Timing Analyzer constraints
  • Requires host clock and agent clock to be synchronous
  • Handles different bus sizes between CPU and memory
  • Requires the frequency of the host clock to be double of the agent clock
  • Has configurable address and data port widths in the host interface