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

3.2.4.2. Agent Mode Operation

In agent mode, the SPI ports behave as shown in the table below.

Table 5.  Agent Mode Port Configurations
Name Direction Description
mosi input Data input from the host
miso output Data output to the host
sclk input Synchronization clock
ss_n input Select signal

In agent mode, the SPI core simply waits for the host to initiate transactions. Before a transaction begins, the agent logic continuously polls the ss_n input. When the host asserts ss_n, the agent logic immediately begins sending the transmit shift register contents to the miso output. The agent logic also captures data on the mosi input, and fills the receive shift register simultaneously. After a word is received by the agent, the host must de-assert the ss_n signal and reasserts the signal again when the next word is ready to be sent.

An intelligent host such as a microprocessor writes data to the txdata registers, so that it is transmitted the next time the host initiates an operation. A host peripheral reads received data from the rxdata register. A host peripheral can enable interrupts to notify the host whenever new data is received, or whenever the transmit buffer is ready for new data.