IIC总线驱动问题

由于准备写一个基于Linux操作系统的IIC总线驱动，所以先把裸机上的程序调试通过后才去开发基于Linux操作系统的，但是有一个小问题，程序都完全按IIC总线时序来书定了，还是有些错误。主要是不能正常定位，即不能选择性读与选择性起始地址后以页的方式进行读取。在这两种方式下，写入到rIICDS地址不能发送出去，一直保存于rIICDS中，所以在对rIICDS进行读时，读到的还是写入到rIICDS中的值。

同时，看了开发板提供的例子，有一点问题，不知道是我理解错了还是什么原因。
一个重大的错误在于rGPECON的设置上。因为IIC的SDA，SCL分别为GPE15与GPE14，而例程在进行GPIO口的初始化时为 rGPECON |= 0xA00000;  这不是把GPE14，GPE15设置为IIC端口，同时，GPE14，GPE15端口没有上端口上拉电阻，而例子中把rGEPUP初始化为 rGPEUP |= 0xC000; 在2440中rGPEUP的有效位只为14位，这样初始有用吗？

下面是我的写的代码，由于本人没有用仿真器，所以不知道错在什么地方，有懂的读者，请帮忙一下。

复制代码 /************************************************ *说明:本程序是S3C2440 IIC总线的一个简单的驱动程序 *     由于本程序比较简单，所以，在此不再进行说明， *     有不懂的读者请自行阅读相关文档。 * *     AT24C08 的地址格式为: 1 0 1 0 A2 P1 P0 W/R *     A2为设备地址位、P1，P0为片内页寻址  LSB=0 写 *     LSB=1 读 * *CPU          ：S3C2440 *编译环境     ：ADS1.2 *开发板       ：MINI2440 *作者         ：soon *部门         : 长沙理工大学 *               计算机与通信工程学院 *               计算机07级04班 *最后修改时间 ：开发中 ************************************************/ #ifndef _MY_IIC_C_ #define _MY_IIC_C_ #include "../include/2440addr.h" #include "../include/2440lib.h" #include "../include/def.h" #include "../include/My_IIC.h" static int seave_gpecon; /*用于保存GPECON的当前值，为恢复GPECON做准备*/ U8 write_buffer[16]; /*写缓冲区*/ U8 read_buffer[16]; /*读缓冲区*/ /*初始化GPIO*/ void _init_gpio(void) {     seave_gpecon = rGPECON;     rGPECON = 0xA0000000;     } /*恢复GPIO口*/ void _resume_gpio(void) {     rGPECON = seave_gpecon; } /*初始化IIC总线*/ void _init_iic(void) {     /*     *IIC应答使能有效、IICCLK = FPCLK/16、     *中断使能、 清除挂取条件、 TXCLK = IICCLK/16     */     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     rIICSTAT = 0x10;     rIICADD = 0x10; } /*写一个字节到指定地址*/ void _byte_write(U8 device_address, U8 word_address, U8 data) {     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     rIICSTAT = (rIICSTAT & 0x0) | (0x1 << 7) | (0x1 << 6);     rIICDS  = device_address;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     while((rIICSTAT & 0x01) == 1);          rIICDS = word_address;     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);          rIICDS = data;     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);     rIICSTAT &= ~(0x1 << 5);     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF); } /*以页的方式写入*/ void _page_write(U8 device_address, U8 word_start_address,U8 *buffer_start_address) {     unsigned int i;          rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     rIICSTAT = (rIICSTAT & 0x0) | (0x1 << 7) | (0x1 << 6);     rIICDS  = device_address;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     while((rIICSTAT & 0x01) == 1);          rIICDS = word_start_address;     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);          for(i = 0; i < 15; i ++){         rIICDS = *(buffer_start_address + i);         rIICCON &= ~(0x1 << 4);         while((rIICSTAT & 0x01) == 1);     }          rIICDS = *(buffer_start_address + i);     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);          rIICSTAT &= ~(0x1 << 5);          rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF); } /*读当前地址单元内容*/ U8 _current_address_read(U8 device_address) {     U8 data;     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);          rIICSTAT = (rIICSTAT &0x0) | (0x1 << 7) | (0 << 6);     rIICDS  = device_address;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     while((rIICSTAT & 0x01) == 1);     rIICCON = (0 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     data = rIICDS;          rIICSTAT &= ~(0x1 << 5);     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);        return data; } /*读指定单元地址内容*/ U8 _random_address_read(U8 device_address, U8 word_address) {     U8 data;          rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     rIICSTAT = (rIICSTAT & 0x0) | (0x1 << 7) | (0x1 << 6);     rIICDS  = device_address & 0xFE;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     while((rIICSTAT & 0x01) == 1);          rIICDS = word_address;     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);               rIICSTAT = (rIICSTAT & 0x0) | (0x1 << 7) | (0 << 6);     rIICDS  = device_address;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);     rIICCON = (0 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     data = rIICDS;          rIICSTAT &= ~(0x1 << 5);     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);        return data; } /*以页读方式读*/ void _sequential_address_read(U8 device_address,U8 word_address,U8 *buffer_start_address) {     unsigned i;               rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     rIICSTAT = (rIICSTAT & 0x0) | (0x1 << 7) | (0x1 << 6);     rIICDS  = device_address & 0xFE;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     while((rIICSTAT & 0x01) == 1);     rIICDS = word_address;     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);          rIICSTAT = (rIICSTAT & 0x0) | (0x1 << 7) | (0 << 6);     rIICDS  = device_address;     rIICSTAT |= (0x1 << 5) | (0x1 << 4);     rIICCON &= ~(0x1 << 4);     while((rIICSTAT & 0x01) == 1);          for(i = 0; i < 15; i ++){         *(buffer_start_address + i) = rIICDS;         rIICCON &= ~(0x1 << 4);         while((rIICSTAT & 0x01) == 1);     }      rIICCON = (0 << 7) | ( 0 << 6) | (0 << 5) | (0xF);     *(buffer_start_address + i) = rIICDS;     rIICSTAT &= ~(0x1 << 5);     rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF); } /*用于延时一小段时间*/ void _delay_time(unsigned int delay_time) {     while(delay_time --); } /*测试程序*/ void _test_iic(void) {     char i;          /*实始化读 写缓冲区*/     for( i = 0; i < 16; i ++){         *(write_buffer + i) = i * 2;         *(read_buffer + i )= 0;         }          /*下面为测试按页写测试*/          _page_write(DEVICE_ADDRESS_WRITE,0,write_buffer);     _delay_time(5);                         for(i = 0; i < 16; i ++){       _byte_write(DEVICE_ADDRESS_WRITE, i,i * 3);      _delay_time(5000);           Uart_Printf("%d   %d\n",i + 1 ,_current_address_read(DEVICE_ADDRESS_READ));      _delay_time(10);           }          /*下面为测试随机地址读*/     for(i = 0; i < 16; i ++){       Uart_Printf("%d\n",_random_address_read(DEVICE_ADDRESS_READ,i));       _delay_time(5);              Uart_Printf("%d\n",_current_address_read(DEVICE_ADDRESS_READ));       _delay_time(5);              }                   /*下面为测试按页读*/     _sequential_address_read(DEVICE_ADDRESS_READ,3,read_buffer);     _delay_time(5);               for(i = 0; i < 16; i ++)         Uart_Printf("%d  %d\n",i + 1,*(read_buffer + i));                    Uart_Printf("\n"); } #endif /************************************************ || || || ||            END My_IIC.c || || || ************************************************/

没有搞过的？在网上找了一天都是一跟开发板上的一样的，真正把AT24C08的两种写入方式，三种读取方式都写出来的没有找到过。

版主呢？看一下吧，版主。在网上的找到的例子几乎都是跟你们提供的开发板的子一样的，这到底是谁抄谁的啊，第一版是谁写的呢？

你这个代码是不是有问题啊？比如rIICCON = (1 << 7) | ( 0 << 6) | (0 << 5) | (0xF);
把第5位设置为0，是不是禁止中断啊，既然禁止了，这一步rIICCON &= ~(0x1 << 4);有什么意义呢？

非中断模式！