参照官方pdf文档做了一个bmp180输出温度气压程序，现在温度能正常，气压就是不准确，怎么调都不行，请大佬们帮忙看看哪里出了问题
[mw_shl_code=c,true]u8 oss=0x01;
bmp_data bmp_180;

static u16 bmp_tworead(u8 msb,u8 lsb)
{
        u8 s1,s2;
        s1=I2C_ReadByte(bmp180_addr,msb);
        s2=I2C_ReadByte(bmp180_addr,lsb);
        return((s1<<8)|(s2&0xFF));
}

void bmp_getcalib(void)
{
        bmp_180.ac1=(short)bmp_tworead(0xAA,0xAB);
        bmp_180.ac2=(short)bmp_tworead(0xAC,0xAD);
        bmp_180.ac3=(short)bmp_tworead(0xAE,0xAF);
        bmp_180.ac4=bmp_tworead(0xB0,0xB1);
        bmp_180.ac5=bmp_tworead(0xB2,0xB3);
        bmp_180.ac6=bmp_tworead(0xB4,0xB5);
        bmp_180.b1=(short)bmp_tworead(0xB6,0xB7);
        bmp_180.b2=(short)bmp_tworead(0xB8,0xB9);
        bmp_180.mb=(short)bmp_tworead(0xBA,0xBB);
        bmp_180.mc=(short)bmp_tworead(0xBC,0xBD);
        bmp_180.md=(short)bmp_tworead(0xBE,0xBF);
       
}


u8 bmp180_init(void)
{
        bmp_getcalib();
        if(I2C_ReadByte(bmp180_addr,0xD0)==0x55)
        {
                return(0);
        }else{return(1);}
}

void bmp_getdata(long *temp,long *pres)
{
        u8 xlsb;
        u16 mlsb;
        long x1,x2,x3,b3,b5,b6,p;
        unsigned long b4,b7;
        I2C_WriteByte(bmp180_addr,0xF4,0x2E);//开始测温度
        delay_ms(5);
        bmp_180.ut=(long)bmp_tworead(0xF6,0xF7);//读出ut
       
       
        x1=(bmp_180.ut-bmp_180.ac6)*bmp_180.ac5/32768;
        x2=bmp_180.mc*2048/(x1+bmp_180.md);
        b5=x1+x2;
        *temp=(b5+8)/16;//计算出温度

        I2C_WriteByte(bmp180_addr,0xF4,0x34+(oss<<6));//开始测气压
        delay_ms(8);
        mlsb=bmp_tworead(0xF6,0xF7);
        xlsb=I2C_ReadByte(bmp180_addr,0xF8);
        bmp_180.up=(mlsb<<8+xlsb)>>(8-oss);//读出up
       
        b6=b5-4000;
        x1=(bmp_180.b2*(b6*b6/4096))/2048;
        x2=bmp_180.ac2*b6/2048;
        x3=x1+x2;
        b3=((bmp_180.ac1*4+x3)<<oss+2)/4;
        x1=bmp_180.ac3*b6/8192;
        x2=(bmp_180.b1*(b6*b6/4096))/65536;
        x3=((x1+x2)+2)/4;
        b4=bmp_180.ac4*(unsigned long)(x3+32768)/32768;
        b7=((unsigned long)bmp_180.up-b3)*(50000>>oss);
        if(b7<0x80000000)
        {
                p=(b7*2)/b4;
        }else
        {
                p=(b7/b4)*2;
        }
        x1=(p/256)*(p/256);
        x1=(x1*3038)/65536;
        x2=(-7357*p)/65536;
        p=p+(x1+x2+3791)/16;
        *pres=p;
       
}[/mw_shl_code]

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