arm读写sja1000错误

只看该作者 · 2009-5-21 19:57

EP9315 arm,sja1000 can，wince5.0
参考周立功magic arm的读写函数
void SJA1000_ReadRegister(UINT8 reg, UINT8 *value)
{
    //g_lpBaseSJA1000[8] = reg;
    //*value = (UINT8)g_lpBaseSJA1000[4];
    //return (*(volatile UCHAR * const)Register);
    WRITE_REGISTER_UCHAR((PUCHAR)&g_lpBaseSJA1000[8], reg);
    *value = READ_REGISTER_UCHAR((PUCHAR)&g_lpBaseSJA1000[4]);
    #ifdef DEBUG
    RETAILMSG(1,(TEXT("read from[0x%02x]=[0x%02x] "),reg,*value));
    #endif
}

void SJA1000_WriteRegister(UINT8 reg, UINT8 value)
{
    //g_lpBaseSJA1000[4] = reg;
    //g_lpBaseSJA1000[8] = value;
    #ifdef DEBUG
    RETAILMSG(1,(TEXT("write to[0x%02x]=[0x%02x] "),reg,value));
    #endif
    WRITE_REGISTER_UCHAR((PUCHAR)&g_lpBaseSJA1000[8], reg);
    WRITE_REGISTER_UCHAR((PUCHAR)&g_lpBaseSJA1000[4], value);
}可以写进sja1000,这个通过写CDR分频系数改变CLKOUT脚的频率，通过示波器得知
读的时候读回来的都是要读数据的地址，好像读得太快了，刚把地址送出，还没等到数据，就读，结果读到地址了，因sja1000地址数据线复用。各位大侠有什么看法。
串口打印信息如下
read from[0x00]=[0x00]
read from[0x01]=[0x01]
read from[0x02]=[0x02]
read from[0x03]=[0x03]
read from[0x04]=[0x04]
read from[0x05]=[0x05]
read from[0x06]=[0x06]
read from[0x07]=[0x07]
read from[0x08]=[0x08]
read from[0x09]=[0x09]