Embedded Peripherals IP User Guide

ID 683130
Date 12/13/2021
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents
1. Introduction 2. Avalon® -ST Multi-Channel Shared Memory FIFO Core 3. Avalon® -ST Single-Clock and Dual-Clock FIFO Cores 4. Avalon® -ST Serial Peripheral Interface Core 5. SPI Core 6. SPI Agent/JTAG to Avalon® Host Bridge Cores 7. Intel eSPI Agent Core 8. eSPI to LPC Bridge Core 9. Ethernet MDIO Core 10. Intel FPGA 16550 Compatible UART Core 11. UART Core 12. JTAG UART Core 13. Intel FPGA Avalon® Mailbox Core 14. Intel FPGA Avalon® Mutex Core 15. Intel FPGA Avalon® I2C (Host) Core 16. Intel FPGA I2C Agent to Avalon® -MM Host Bridge Core 17. Intel FPGA Avalon® Compact Flash Core 18. EPCS/EPCQA Serial Flash Controller Core 19. Intel FPGA Serial Flash Controller Core 20. Intel FPGA Serial Flash Controller II Core 21. Intel FPGA Generic QUAD SPI Controller Core 22. Intel FPGA Generic QUAD SPI Controller II Core 23. Interval Timer Core 24. Intel FPGA Avalon FIFO Memory Core 25. On-Chip Memory (RAM and ROM) Intel FPGA IP 26. On-Chip Memory II (RAM or ROM) Intel FPGA IP 27. Optrex 16207 LCD Controller Core 28. PIO Core 29. PLL Cores 30. DMA Controller Core 31. Modular Scatter-Gather DMA Core 32. Scatter-Gather DMA Controller Core 33. SDRAM Controller Core 34. Tri-State SDRAM Core 35. Video Sync Generator and Pixel Converter Cores 36. Intel FPGA Interrupt Latency Counter Core 37. Performance Counter Unit Core 38. Vectored Interrupt Controller Core 39. Avalon® -ST Data Pattern Generator and Checker Cores 40. Avalon® -ST Test Pattern Generator and Checker Cores 41. System ID Peripheral Core 42. Avalon® Packets to Transactions Converter Core 43. Avalon® -ST Multiplexer and Demultiplexer Cores 44. Avalon® -ST Bytes to Packets and Packets to Bytes Converter Cores 45. Avalon® -ST Delay Core 46. Avalon® -ST Round Robin Scheduler Core 47. Avalon® -ST Splitter Core 48. Avalon® -MM DDR Memory Half Rate Bridge Core 49. Intel FPGA GMII to RGMII Converter Core 50. Intel FPGA MII to RMII Converter Core 51. Intel FPGA HPS GMII to TSE 1000BASE-X/SGMII PCS Bridge Core 52. Intel FPGA HPS EMAC to Multi-rate PHY GMII Adapter Core 53. Intel FPGA MSI to GIC Generator Core

4.1.2. Operation

The Avalon® -ST SPI core waits for the nSS signal to be asserted low, signifying that the SPI host is initiating a transaction. The core then starts shifting in bits from the input signal mosi. The core packs the bits received on the SPI to bytes and checks for the following special characters:
  • 0x4a—Idle character. The core drops the idle character.
  • 0x4d—Escape character. The core drops the escape character, and XORs the following byte with 0x20.

    For each valid byte of data received, the core asserts the valid signal on its Avalon® -ST source interface and presents the byte on the interface for one clock cycle.

    At the same time, the core shifts data out from the Avalon® -ST sink to the output signal miso beginning with from the most significant bit. If there is no data to shift out, the core shifts out idle characters (0x4a). If the data is a special character, the core inserts an escape character (0x4d) and XORs the data with 0x20.

    The data shifts into and out of the core in the direction of MSB first.

Figure 6. SPI Transfer Protocol
Table 13.  SPI Transfer Protocol Specification
Symbol Description Minimum Maximum Unit
TL The worst recovery time of sclk with respect with nSS. ½ SPI clock - Clock cycle
TT The worst hold time for MOSI and MISO data. ½ SPI clock -
TI The minimum width of a reset pulse required by Intel FPGA families. 1 SPI clock -