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

12.4.1.3. Driver Examples

The figure below demonstrates writing to a Mailbox. For this example, assume that the hardware system has two processors communicating via Mailboxes. The system includes two Mailbox cores, which provides two-way communication between the processors.

Sender Processor Using Mailbox to Send a Message.

#include <stdio.h>
#include "altera_avalon_mailbox_simple.h"
#include "altera_avalon_mailbox_simple_regs.h"
#include "system.h"

/* example callback function from users*/
void tx_cb (void* report, int status) {  
	if (!status) {    
	   printf (“Transfer done”);  
	} else {    
	   printf (“error in transfer”);  
	}

int main_sender()
{
alt_u32 message[2] = {0x00001111, 0xaa55aa55};
int timeout     = 50000;
alt_u32 status;
alt_avalon_mailbox_simple_dev* mailbox_sender; 

/* Open mailbox on sender processor */
mailbox_sender = alt_avalon_mailbox_open("/dev/mailbox_simple_0", tx_cb, NULL);   

	if (!mailbox_sender){        
		printf ("FAIL: Unable to open mailbox_simple");         
		return 1;    
		} 

	/* Send a message to the other processor using interrupt */
	altera_avalon_mailbox_send (mailbox_sender, message, 0, ISR);

	/* Using polling method to send a message, with infinite timeout */  
		timeout = 0;  
		status = altera_avalon_mailbox_send (mailbox_sender, message, timeout, POLL);

		if (status) {    
			printf (“error in transfer”);  
		} else {    
			printf (“Transfer done”);  
		}

	/* Closing mailbox device and de-registering interrupt handler and callback */  
	altera_avalon_mailbox_close (mailbox_sender);  
	return 0;
	}

Receiver Processor Waiting for Message.

#include <stdio.h>
#include "altera_avalon_mailbox_simple.h"
#include "altera_avalon_mailbox_simple_regs.h"
#include "system.h"

void rx_cb (void* message) {  
	/* Get message read from mailbox */  
	alt_u32* data = alt_u32* message;  
	if (message!= NULL) {    
		printf (“Message received”);  
	} else {    
	  printf (“Incomplete receive”);  
	}

int main_receiver()
{
alt_u32* message[2];
int timeout     = 50000;
alt_avalon_mailbox_simple_dev* mailbox_rcv;

	/* This example is running on receiver processor */  
	mailbox_rcv = alt_avalon_mailbox_open("/dev/mailbox_simple_1", NULL, rx_cb);  
	if (!mailbox_rcv){    
		printf ("FAIL: Unable to open mailbox_simple");    
		return 1;  
	} 

	/* For interrupt disable system */  
	altera_avalon_mailbox_retrieve_poll (mailbox_rcv,message, timeout)  
	
	if (message == NULL)
	printf (“Receive Error”); 
	else 
	printf (“Message received with Command 0x%x and Message 0x%x\n”, message[0], message[1]);  
	

altera_avalon_mailbox_close (mailbox_rcv);
return 0;
}