mega/drivers/twi/master_example/twi_master_example.c File Reference

TWi master example for megaRF device.

Copyright (c) 2014-2018 Microchip Technology Inc. and its subsidiaries.

#include "asf.h"
#include <conf_twi.h>
#include <conf_board.h>

Macros
#define	TWI_EXAMPLE   &TWBR

Functions
int	main (void)
	TWI Master Example Main. More...

Slave EEPROM memory Test Pattern Constants
#define	PATTERN_TEST_LENGTH   sizeof(test_pattern)
const uint8_t	test_pattern []
const uint8_t	slave_mem_addr [SLAVE_MEM_ADDR_LENGTH]

#define PATTERN_TEST_LENGTH   sizeof(test_pattern)

Referenced by main().

#define TWI_EXAMPLE   &TWBR

Referenced by main().

int main

(

void

)

TWI Master Example Main.

Main function.

The master example begins by initializing required board resources. The system clock, basic GPIO pin mapping, and interrupt vectors are established.

A memory location on a TWI slave is written with a fixed test pattern which is then read back into a separate buffer. As a basic sanity check, the original write-buffer values are compared with values read from the slave to a separate buffer. An LED on the development board is illuminated when there is a match between the written and read data.

Returns

Nothing.

The SAM3X_EK, SAM3X Arduino board and SAM4C_EK use two bytes length internal address EEPROM.

References twi_package_t::addr, twi_master_options_t::baud_reg, board_init(), data_received, delay_ms, LED_On, PATTERN_TEST_LENGTH, SLAVE_BUS_ADDR, slave_mem_addr, SLAVE_MEM_ADDR_LENGTH, twi_master_options_t::speed, sysclk_enable_peripheral_clock(), sysclk_get_cpu_hz(), sysclk_init(), test_pattern, TWI_CLOCK_RATE, TWI_EXAMPLE, twi_master_init(), twi_master_read(), twi_master_write(), and TWI_SUCCESS.

const uint8_t slave_mem_addr[SLAVE_MEM_ADDR_LENGTH]

Initial value:

= {
    0x00,
}

Referenced by main().

const uint8_t test_pattern[]

Initial value:

= {
    0x05,
    0x15,
    0x25,
    0x35,
    0x45,
    0x55,
    0x65,
    0x75,
}