電腦從串口RS232收到壹些ASCII碼的文字：“0”、“1”“2”等，用C51編程，使“0”轉成數字0，“1”轉成1

ASCII碼a b c d等,它們的十六進制碼為0x61,0x62,0x63,0x64等

ASCII碼A B C D等,它們的十六進制碼為0x61,0x62,0x63,0x64等

所以轉換函數為

unsigned char convert(unsigned char a)

{

unsigned char b;

if((a>0x30)&&(a<0x39))

{

b=a-0x30;

}

if((a>=0x41)&&(a<=0x46))

{

b=(a-0x41)+10;

}

if((a>=0x61)&&(a<=0x66))

{

b=a-0x61;

}

return b;

}