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

8.2.1. MDIO Frame Format (Clause 45)

The MDIO core communicates with the external PHY device using frames. A complete frame is 64 bits long and consists of 32-bit preamble, 14-bit command, 2-bit bus direction change, and 16-bit data. Each bit is transferred on the rising edge of the management data clock (MDC). The PHY management interface supports the standard MDIO specification (IEEE802.3 Ethernet Standard Clause 45).
Figure 29. MDIO Frame Format (Clause 45)
Table 45.  MDIO Frame Field Descriptions—Clause 45
Field Name Description
PRE Preamble. 32 bits of logical 1 sent prior to every transaction.
ST The start of frame for indirect access cycles is indicated by the <00> pattern. This pattern assures a transition from the default one and identifies the frame as an indirect access.
OP The operation code field indicates the following transaction types:

00 indicates that the frame payload contains the address of the register to access.

01 indicates that the frame payload contains data to be written to the register whose address was provided in the previous address frame.

11 indicates that the frame is a read operation.

The post-read-increment-address operation <10> is not supported in this frame.

PRTAD The port address (PRTAD) is 5 bits, allowing 32 unique port addresses. Transmission is MSB to LSB. A station management entity (STA)16 must have a prior knowledge of the appropriate port address for each port to which it is attached, whether connected to a single port or to multiple ports.
DEVAD The device address (DEVAD) is 5 bits, allowing 32 unique MDIO manageable devices (MMDs)17 per port. Transmission is MSB to LSB.
TA The turnaround time is a 2-bit time spacing between the device address field and the data field of a management frame to avoid contention during a read transaction.

For a read transaction, both the STA and the MMD remain in a high-impedance state (Z) for the first bit time of the turnaround. The MMD drives a 0 during the second bit time of the turnaround of a read or postread-increment-address transaction.

For a write or address transaction, the STA drives a 1 for the first bit time of the turnaround and a 0 for the second bit time of the turnaround.

REGAD/

Data

The register address (REGAD) or data field is 16 bits. For an address cycle, it contains the address of the register to be accessed on the next cycle. For the data cycle of a write frame, the field contains the data to be written to the register. For a read frame, the field contains the contents of the register. The first bit transmitted and received is bit 15.
Idle The idle condition on MDIO is a high-impedance state. All tri-state drivers are disabled and the MMDs pullup resistor pulls the MDIO line to a one.
16 The device driving the MDIO bus is identified as the Station Management Entity (STA).
17 The target devices managed by the MDC are referred as MDIO Manageable Devices (MMDs).