< -c%.o : %.c$(CC) $(CPPFLAGS) $(CFLAGS) -o $@ $< -cclean:rm *.o *.elf *.bin *.dis mkx210 -fcd lib; make clean; cd ..
移植的库中的文件：lib/：
objs := div64.o lib1funcs.o ctype.o muldi3.o printf.o string.o vsprintf.olibc.a: $(objs)${AR} -r -o $@ $^%.o:%.c${CC} $(CPPFLAGS) $(CFLAGS) -c -o $@ $<%.o:%.S${CC} $(CPPFLAGS) $(CFLAGS) -c -o $@ $
修改 uart.c 文件中的串口输出函数：
$ cat uart.c#define GPA0CON0xE0200000#define UCON00xE2900004#define ULCON00xE2900000#define UMCON00xE290000C#define UFCON00xE2900008#define UBRDIV00xE2900028#define UDIVSLOT00xE290002C#define UTRSTAT00xE2900010#define UTXH00xE2900020#define URXH00xE2900024#define rGPA0CON(*(volatile unsigned int *)GPA0CON)#define rUCON0(*(volatile unsigned int *)UCON0)#define rULCON0(*(volatile unsigned int *)ULCON0)#define rUMCON0(*(volatile unsigned int *)UMCON0)#define rUFCON0(*(volatile unsigned int *)UFCON0)#define rUBRDIV0(*(volatile unsigned int *)UBRDIV0)#define rUDIVSLOT0(*(volatile unsigned int *)UDIVSLOT0)#define rUTRSTAT0(*(volatile unsigned int *)UTRSTAT0)#define rUTXH0(*(volatile unsigned int *)UTXH0)#define rURXH0(*(volatile unsigned int *)URXH0)/**************************************************************************************/#define ULCON0_FUNC_NO_PARITY_MODE(0b000 << 3)// 无校验#define ULCON0_FUNC_NUMBER_STOP_0_BIT(0b0<< 2)// Stop bit: 0#define ULCON0_FUNC_WORLD_LENGTH_8_BIT(0b11<< 0)// 8 位数据位/**************************************************************************************/#define UCON0_FUNC_CLOCK_SELECTION_PLCK(0b0<<10)//选择PCLK#define UCON0_FUNC_LOOPBACK_MODE_NORMAL(0b0<< 5)//正常模式#define UCON0_FUNC_TX_MODE_POLLING(0b01<< 2)//轮询模式#define UCON0_FUNC_RX_MODE_POLLING(0b01<< 0)//轮询模式/**************************************************************************************/#define UFCON0_FUNC_FIFO_DISABLE(0b0<< 0)//禁止 FIFO 模式/**************************************************************************************/#define UTRSTAT0_FUNC_TRANSMITTER_EMPTY(0b1<< 2)//发送缓冲区为空#define BIT_LOCATION_UTRSTAT0_FUNC_TRANSMITTER_EMPTY(0b1<< 2)//发送缓冲器状态位#define UTRSTAT0_FUNC_RECEIVE_BUFFER_DATA_READY(0b1<< 0)//接收缓冲区已接收到数据#define BIT_LOCATION_UTRSTAT0_FUNC_RECEIVE_BUFFER_DATA_READY(0b1<< 0)//接收缓冲区状态位/**************************************************************************************/#define BIT_WIDTH_GPA0(4)#define GPA0_0_FUNC_INPUT(0x0 << 0 * BIT_WIDTH_GPA0)#define GPA0_0_FUNC_OUTPUT(0x1 << 0 * BIT_WIDTH_GPA0)#define GPA0_0_FUNC_UART0RXD(0x2 << 0 * BIT_WIDTH_GPA0)#define GPA0_0_FUNC_GPA0_INT0(0Xf << 0 * BIT_WIDTH_GPA0)#define GPA0_1_FUNC_INPUT(0x0 << 1 * BIT_WIDTH_GPA0)#define GPA0_1_FUNC_OUTPUT(0x1 << 1 * BIT_WIDTH_GPA0)#define GPA0_1_FUNC_UART0TXD(0x2 << 1 * BIT_WIDTH_GPA0)#define GPA0_1_FUNC_GPA0_INT1(0Xf << 1 * BIT_WIDTH_GPA0)#define BIT_LOCATION_GPA0_CON0(0xf << 0 * BIT_WIDTH_GPA0)#define BIT_LOCATION_GPA0_CON1(0xf << 1 * BIT_WIDTH_GPA0)/**************************************************************************************///串口初始化程序void uart_init(void){// 初始化 TX RX 对应的 GPIO 引脚rGPA0CON &= ~(BIT_LOCATION_GPA0_CON0 | BIT_LOCATION_GPA0_CON1);rGPA0CON |= GPA0_0_FUNC_UART0RXD| GPA0_1_FUNC_UART0TXD;//几个关键寄存器的设置rULCON0 = ULCON0_FUNC_NO_PARITY_MODE | ULCON0_FUNC_NUMBER_STOP_0_BIT | ULCON0_FUNC_WORLD_LENGTH_8_BIT;rUCON0 = UCON0_FUNC_CLOCK_SELECTION_PLCK | UCON0_FUNC_LOOPBACK_MODE_NORMAL | UCON0_FUNC_TX_MODE_POLLING | UCON0_FUNC_RX_MODE_POLLING;rUMCON0 = 0;rUFCON0 = UFCON0_FUNC_FIFO_DISABLE;#if 0//波特率设置DIV_VAL = (PCLK / (bps X 16) ) - 1//PCLK_PSYS 用 66MHz 算DIV_VAL = (66 X 10^6 / (115200 X 16)) - 1 = 34.807//小数是 0.8，0.8 x 16 = 12.8rUBRDIV0 = 34;//12 0xDDDD(1101_1101_1101_1101b)//13 0xDFDD(1101_1111_1101_1101b)rUDIVSLOT0 =0xDDDD;#endif//PCLK_PSYS 用 66.7MHz 算DIV_VAL = (66.7 X 10^6 / (115200 X 16)) - 1 = 35.187//小数是 0.18，0.18 x 16 = 2.88rUBRDIV0 = 35;//2 0x0808(0000_1000_0000_1000b)//3 0x0888(0000_1000_1000_1000b)rUDIVSLOT0 =0x0808;}//串口接收程序，轮询方式，接收一个字节void putc(char c){//串口发送一个字符，其实就是把一个字节丢到发送缓冲区中去//因为串口控制器发送 1 个字节的速度远远低于 CPU 的速度，所以 CPU 发送1个字节前必须//确认串口控制器当前缓冲区是空的（意思就是串口已经发完了上一个字节）//如果缓冲区非空则位为0，此时应该循环，直到位为1while ((rUTRSTAT0 & BIT_LOCATION_UTRSTAT0_FUNC_TRANSMITTER_EMPTY) != UTRSTAT0_FUNC_TRANSMITTER_EMPTY) ;rUTXH0 = c;}//串口接收程序，轮询方式，接收一个字节char getc(void){while ((rUTRSTAT0 & BIT_LOCATION_UTRSTAT0_FUNC_RECEIVE_BUFFER_DATA_READY) != UTRSTAT0_FUNC_RECEIVE_BUFFER_DATA_READY) ;returnrURXH0 & 0xff;}