Arduino驱动MAX7219四位数码管显示时间

Arduino驱动MAX7219四位数码管显示时间

默认使用Pin 2为MOSI（数据发送）引脚，Pin 3为CS（片选）引脚，Pin 4为SCLK（时钟）引脚，如有需要请修改代码前三行的define。

#define MO 2

#define CS 3

#define CLK 4

static int time_h = 21, time_m =25, time_s = 30; //此刻时间：时，分，秒

int alarm_clock_h = 8, alarm_clock_m = 00; //闹钟时间

unsigned long time = 0;

unsigned char buffer_led[5] = { 0x00,};//缓存

void SPI_init(void) //初始化SPI引脚

{

pinMode(CLK, OUTPUT);

pinMode(MO, OUTPUT);

pinMode(CS, OUTPUT);

digitalWrite(CS, HIGH);

digitalWrite(CLK, LOW);

digitalWrite(MO, HIGH);

}

void SPI_send(unsigned char reg, unsigned char data) //spi单向16位数据发送{

int x;

/*

Serial.print("reg = ");

Serial.print(reg, HEX);

Serial.print(" data = ");

Serial.println(data, HEX);

*/

digitalWrite(CS, LOW);

for (x = 0; x < 8; x++)

{

digitalWrite(MO, 0x80 & (reg << x)); //高位在前

digitalWrite(CLK, HIGH);

digitalWrite(CLK, LOW);

}

for (x = 0; x < 8; x++)

{

digitalWrite(MO, 0x80 & (data << x)); //高位在前 digitalWrite(CLK, HIGH);

digitalWrite(CLK, LOW);

}

digitalWrite(CS, HIGH);

}

void lcd_init(void)//初始化Max7219配置

{

SPI_send(0x0b, 0x07); //scan-limit

SPI_send(0x09, 0xff); //decode mode all

SPI_send(0x0c, 0x01); //shutdown off

SPI_send(0x0f, 0x00); //off display test

SPI_send(0x0a, 0x04); //intensity

delay(100);

}

void clear(void)//清除显示

{

for (int i = 1; i <= 8; i++)

{

SPI_send(i, 0x0F);

}

}

void led_display(void)//显示时间

{

char cache = 0x00;

if ((time_h / 10) == 0)buffer_led[0] = 0x00;

else buffer_led[0] = time_h / 10;

buffer_led[1] = time_h % 10 | 0x01;

buffer_led[2] = time_m / 10;

buffer_led[3] = time_m % 10;

SPI_send(8, buffer_led[0]);

SPI_send(7, buffer_led[1]);

SPI_send(6, 0x0a);

SPI_send(5, buffer_led[2]);

SPI_send(4, buffer_led[3]);

SPI_send(3, 0x0a);

SPI_send(2, time_s / 10);

SPI_send(1, time_s % 10);

}

void get_time()//获取时间并更新显示

{

static char ss = 1;

static unsigned long time_cc = 0;

if ((millis() - time_cc) > 1000 | millis() < 150)//秒

{

if (millis() <= 200) //若系统计时器溢出时时间，time_cc重计

{

time_cc = millis();

time_s ++;

delay(150);

}

else if (millis() > 200)//秒

{

time_s += (millis() - time_cc) / 1000;

// time_cc = millis()-990; //时间快进

time_cc = millis();

buffer_led[4] = (0x01 & ss) << 5;

ss = ~ss;

}

if (time_s > 59) //分

{

if (time_s - 60 > 1)//如果有延时间隔导致秒钟大于60秒，进行分钟缺失补偿 {

time_m += time_s / 60;

if (time_s % 60 == 0)time_m--;

time_s = time_s - (time_s / 60) * 60;

}

else time_s = 0;

time_m++;

buffer_led[4] = 0x80;

if (time_m > 59)//时

{

time_h++;

time_m = (time_m - 60);

buffer_led[4] = 0xf0;

}

if (time_h > 23)

{

time_h = 0;