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

22.2.3. Avalon® -MM Write Agent to Avalon® -ST Source

In this configuration, the input is an Avalon® -MM write agent with a width of 32 bits as shown in the FIFO with Avalon® -MM Input Interface and Avalon® -ST Output Interface figure below. The Avalon® -ST output (source) data width must also be 32 bits. You can configure output interface parameters, including: bits per symbol, symbols per beat, and the width of the channel and error signals. The FIFO core performs the endian conversion to conform to the output interface protocol.

The signals that comprise the output interface are mapped into bits in the Avalon® address space. If Allow backpressure is turned on, the input interface asserts waitrequest to indicate that the FIFO core does not have enough space for the transaction to complete.

Figure 75. FIFO with Avalon® -MM Input Interface and Avalon® -ST Output Interface
Table 273.  Bit Field
Offset 31         24 23   19 18     16 15     13 12     8 7     4 3 2 1 0
base + 0 Symbol 3 Symbol 2 Symbol 1 Symbol 0
base + 1 reserved reserved error reserved channel reserved empty EOP SOP
Table 274.  Memory Map
Offset Bits Field Description
0 31:0 SYMBOL_0, SYMBOL_1, SYMBOL_2 .. SYMBOL_n Packet data. The value of the Symbols per beat parameter specifies the number of fields in this register; Bits per symbol specifies the width of each field.
1 0 SOP The value of the startofpacket signal.
1 EOP The value of the endofpacket signal.
6:2 EMPTY The value of the empty signal.
7 Reserved.
15:8 CHANNEL The value of the channel signal. The number of bits occupied corresponds to the width of the signal. For example, if the width of the channel signal is 5, bits 8 to 12 are occupied and bits 13 to 15 are unused.
23:16 ERROR The value of the error signal. The number of bits occupied corresponds to the width of the signal. For example, if the width of the error signal is 3, bits 16 to 18 are occupied and bits 19 to 23 are unused.
31:24 Reserved.

If Enable packet data is turned off, the Avalon® -MM write host writes all data at address offset 0 repeatedly to push data into the FIFO core.

If Enable packet data is turned on, the Avalon® -MM write host starts by writing the SOP, ERROR (optional), CHANNEL (optional), EOP, and EMPTY packet status information at address offset 1. Writing to address offset 1 does not push data into the FIFO core. The Avalon® -MM host then writes packet data to address offset 0 repeatedly, pushing 8-bit symbols into the FIFO core. Whenever a valid write occurs at address offset 0, the data and its respective packet information is pushed into the FIFO core. Subsequent data is written at address offset 0 without the need to clear the SOP field. Rewriting to address offset 1 is not required each time if the subsequent data to be pushed into the FIFO core is not the end-of-packet data, as long as ERROR and CHANNEL do not change.

At the end of each packet, the Avalon® -MM host writes to the address at offset 1 to set the EOP bit to 1, before writing the last symbol of the packet at offset 0. The write host uses the empty field to indicate the number of unused symbols at the end of the transfer. If the last packet data is not aligned with the symbols per beat, the EMPTY field indicates the number of empty symbols in the last packet data. For example, if the Avalon® -ST interface has symbols per beat of 4, and the last packet only has 3 symbols, the empty field will be 1, indicating that one symbol (the least significant symbol in the memory map) is empty.