Embedded Peripherals IP User Guide

ID 683130
Date 10/18/2021
Public

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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) Core 26. On-Chip Memory II (RAM or ROM) 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

5.2.4.1. Host Mode Operation

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

Table 14.  Host Mode Port Configurations
Name Direction Description
mosi output Data output to agent(s)
miso input Data input from agent(s)
sclk output Synchronization clock to all agents
ss_nM output Agent select signal to agent M, where M is a number between 0 and 31.

In host mode, an intelligent host (for example, a microprocessor) configures the SPI core using the control and slaveselect registers, and then writes data to the txdata buffer to initiate a transaction. A host peripheral can monitor the status of the transaction by reading the status register. A host peripheral can enable interrupts to notify the host whenever new data is received (for example, a transfer has completed), or whenever the transmit buffer is ready for new data.

The SPI protocol is full duplex, so for every transaction both sends and receives data at the same time. The host transmits a new data bit on the mosi output and the agent drives a new data bit on the miso input for each active edge of sclk. The SPI core divides the Avalon® -MM system clock using a clock divider to generate the sclk signal.

When the SPI core is configured to interface with multiple agents, the core has one ss_n signal for each agent. During a transfer, the host asserts ss_n to each agent specified in the slaveselect register. Note that there can be no more than one agent transmitting data during any particular transfer, or else there will be a contention on the miso input. The number of agent devices is specified at system generation time.