接着折腾了下串口 只是简单实现发送功能
首先找到引脚关系，这里就不贴原理图了 串口1的引脚是 gpio_a0的低两位 在这里只需要配置 TX 和RX
接下来就是配置串口的参数 ULCONn：数据位 奇偶校验 停止位 跟上位机配置成一样就好 按照这个 普通模式
ulcon = 0b0000011 = 0x03
接着设置模式寄存器 UCON 设置
uncon = 0x0101 =0x05
其他默认都是关的 先不管 接下来配置波特率 时钟频率位于PSYS 66.5M 按照公式 DIV_VAL = (66500000 / (115200 x 16)) -1 = 36.07 -1 = 35.07
0.07*16 = 1.12 == 1 查表 UDIVSLOT=0x80
代码区
//cpu_io.h #ifndef _S5PV210_CPU_H #define _S5PV210_CPU_H #define _REG(adr) (*(volatile unsigned int *)(adr)) #define readb(adr) (*(volatile unsigned char *)(adr)) #define readw(adr) (*(volatile unsigned short *)(adr)) #define readl(adr) (*(volatile unsigned int *)(adr)) #define writeb(value,adr) ((*(volatile unsigned char *)(adr))=(value)) #define writew(value,adr) ((*(volatile unsigned short *)(adr))=(value)) #define writel(value,adr) ((*(volatile unsigned int*)(adr))=(value)) #endif //gpio.h #ifndef _ASM_ARCH_GPIO_H #define _ASM_ARCH_GPIO_H #define S5PV210_GPIOBASE (0XE0200000) #define S5PV210_UARTBASE (0xE2900000) struct s5pc210_gpio_bank { unsigned int con; unsigned int dat; unsigned int pud; unsigned int drv; unsigned int con_pdn; unsigned int pud_pdn; unsigned char res1[8]; }; struct s5pv210_gpio { struct s5pc210_gpio_bank gpio_a0; struct s5pc210_gpio_bank gpio_a1; struct s5pc210_gpio_bank gpio_b; struct s5pc210_gpio_bank gpio_c0; struct s5pc210_gpio_bank gpio_c1; struct s5pc210_gpio_bank gpio_d0; struct s5pc210_gpio_bank gpio_d1; struct s5pc210_gpio_bank gpio_e0; struct s5pc210_gpio_bank gpio_e1; struct s5pc210_gpio_bank gpio_f0; struct s5pc210_gpio_bank gpio_f1; struct s5pc210_gpio_bank gpio_f2; struct s5pc210_gpio_bank gpio_f3; struct s5pc210_gpio_bank gpio_g0; struct s5pc210_gpio_bank gpio_g1; struct s5pc210_gpio_bank gpio_g2; struct s5pc210_gpio_bank gpio_g3; struct s5pc210_gpio_bank gpio_i; struct s5pc210_gpio_bank gpio_j0; struct s5pc210_gpio_bank gpio_j1; struct s5pc210_gpio_bank gpio_j2; struct s5pc210_gpio_bank gpio_j3; struct s5pc210_gpio_bank gpio_j4; }; struct s5pc210_uart_bank { unsigned int ulcon; unsigned int ucon; unsigned int ufcon; unsigned int umcon; unsigned int utrstat; unsigned int uerstat; unsigned int ufstat; unsigned int umstat; unsigned char utxh; unsigned char res1[3]; unsigned char urxh; unsigned char res2[3]; unsigned int ubrdiv; unsigned short udivslot; unsigned char res3[2]; unsigned char res4[0x3d0]; }; #endif //uart.h #ifndef _UART_LCQ_H #define _UART_LCQ_H void uart0_init(void); void uart0_sendchar(char c); void uart0_sendstr(const char *str); #endif //uart.c #include "uart.h" #include "cpu_io.h" #include "gpio.h" void uart0_init(void) { struct s5pc210_uart_bank *uart_base = (struct s5pc210_uart_bank *)S5PV210_UARTBASE; struct s5pv210_gpio *gpio_base = (struct s5pv210_gpio *)S5PV210_GPIOBASE; unsigned int var; //引脚配置 var = readl(&gpio_base->gpio_a0.con); var &= ~0xff; var |= 0x22; writel(var, &gpio_base->gpio_a0.con); //uart 参数配置 _REG(&uart_base->ulcon) = 0x3; /*8位1位停止位*/ _REG(&uart_base->ucon) = 0x5;/*使能发送接收*/ _REG(&uart_base->ubrdiv) = 35; _REG(&uart_base->udivslot) = 0x80; } void uart0_sendchar(char c) { struct s5pc210_uart_bank *uart_base = (struct s5pc210_uart_bank *)S5PV210_UARTBASE; //等待上次发送完成 while(!(_REG(&uart_base->utrstat)&(0x1<<2))); //发送 _REG(&uart_base->utxh) =c; } void uart0_sendstr(const char *str) { while(*str) { uart0_sendchar(*str); str++; } } char uart0_getchar(void) { struct s5pc210_uart_bank *uart_base = (struct s5pc210_uart_bank *)S5PV210_UARTBASE; //等待上次发送完成 while(!(_REG(&uart_base->utrstat)&(0x1<<0))); //发送 return _REG(&uart_base->utxh); }今天之所以折腾到现在 是因为我用一个转串口接到一个已经转成串口的引脚上去了 真是脑残
