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

3.4.3.3. status Register

The status register consists of bits that indicate status conditions in the SPI core. Each bit is associated with a corresponding interrupt-enable bit in the control register, as discussed in the Control Register section. A host peripheral can read status at any time without changing the value of any bits. Writing status does clear the ROE, TOE and E bits.

Table 10.  status Register Bits
# Name Description
3 ROE Receive-overrun error

The ROE bit is set to 1 if new data is received while the rxdata register is full (that is, while the RRDY bit is 1). In this case, the new data overwrites the old. Writing to the status register clears the ROE bit to 0.

4 TOE Transmitter-overrun error

The TOE bit is set to 1 if new data is written to the txdata register while it is still full (that is, while the TRDY bit is 0). In this case, the new data is ignored. Writing to the status register clears the TOE bit to 0.

5 TMT Transmitter shift-register empty

In host mode, the TMT bit is set to 0 when a transaction is in progress and set to 1 when the shift register is empty.

In agent mode, the TMT bit is set to 0 when the agent is selected (SS_n is low) or when the SPI Agent register interface is not ready to receive data.

6 TRDY Transmitter ready

The TRDY bit is set to 1 when the txdata register is empty.

7 RRDY Receiver ready

The RRDY bit is set to 1 when the rxdata register is full.

8 E Error

The E bit is the logical OR of the TOE and ROE bits. This is a convenience for the programmer to detect error conditions. Writing to the status register clears the E bit to 0.

9 EOP End of Packet

The EOP bit is set when the End of Packet condition is detected. The End of Packet condition is detected when either the read data of the rxdata register or the write data to the txdata register is matching the content of the eop_value register.