我想串口程序應(yīng)該是ARM程序中最簡單的了吧。盡管如此，做個記錄吧 。

具體設(shè)置如下：

本文引用地址：http://www.biyoush.com/article/201611/317136.htm

#define ULCON0 (*((volatile unsigned long *)0x7F005000))

#define UCON0 (*((volatile unsigned long *)0x7F005004))

#define UFCON0 (*((volatile unsigned long *)0x7F005008))

#define UMCON0 (*((volatile unsigned long *)0x7F00500C))

#define UTRSTAT0 (*((volatile unsigned long *)0x7F005010))

#define UFSTAT0 (*((volatile unsigned long *)0x7F005018))

#define UTXH0 (*((volatile unsigned char *)0x7F005020))

#define URXH0 (*((volatile unsigned char *)0x7F005024))

#define UBRDIV0 (*((volatile unsigned short *)0x7F005028))

#define UDIVSLOT0 (*((volatile unsigned short *)0x7F00502C))

#define GPACON (*((volatile unsigned long *)0x7F008000))

void init_uart(void)

{

GPACON &= ~0xff;

GPACON |= 0x22;

/* ULCON0 */

ULCON0 = 0x3; /* 數(shù)據(jù)位:8, 無較驗, 停止位: 1, 8n1 */

UCON0 = 0x5; /* 使能UART發(fā)送、接收 */

UFCON0 = 0x01; /* FIFO ENABLE */

UMCON0 = 0;

/* 波特率 */

/* DIV_VAL = (PCLK / (bps x 16 ) ) - 1

*PCLK = 66.5MHz

* bps = 115200

* DIV_VAL = (66500000 / (115200 x 16 ) ) - 1

* = 35.08

*/

UBRDIV0 = 35;

/* x/16 = 0.08

* x = 1

*/

UDIVSLOT0 = 0x1;

}

char getchar(void)

{

while ((UFSTAT0& (1<<6)) == 0 && (UFSTAT0& 0x3f) == 0);

return URXH0;

}

void putchar(char c)

{

while ((UFSTAT0 & (1<<14)) );

UTXH0 = c;

}

在主函數(shù)中調(diào)用上面的串口初始化函數(shù)，接收字符串函數(shù)和發(fā)送字符穿函數(shù)，如下，通過鍵盤在串口助手中向串口發(fā)送字符，則會有“輸入字符+1”顯示在終端上。

int main()

{

char c;

init_uart();

while (1)

{

c = getchar();

putchar(c+1);

}

return 0;

}

更改主函數(shù)與Uart.c函數(shù)，實現(xiàn)你想要的功能：

int main()

{

char c;

char* str = "---hello uart-arm-----rn";

char* addition ="---addition operation----rn";

char* of1 = "a. hellorn";

char* of2 = "b. what is your namern";

char* of3 = "c. beliefrn";

char a,b ; char sum;

char choice;

init_uart();

//print str

c = getchar();

putchar(c+1);

putstr(str);

//addition operation

putstr(addition);

putstr(of1);

putstr(of2);

putstr(of3);

while(1){

choice = getchar();

if(choice ==a)

putstr("hellorn");

else

if (choice ==b)

putstr("what is your namern");

else

if (choice ==c)

putstr("beliefrn");

else

putstr("no optionrn");

}}

上面函數(shù)相當(dāng)于一個簡單的菜單選擇。 輸出如下，以下結(jié)果是依次從鍵盤輸入a,b,c,d,e之后的結(jié)果