i want to write to xdata register with keypad and see the address and data on lcd..... how i can to write "scanf" function for LCD ????

for example:

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void writereg() /* -------- write data to specified register --------- */
{
uchar Add, Data;
printf("\nEnter Address (hex): "); /* Get Address & Data */
scanf("%bx", &Add);
printf("DATA (hex): ");
scanf("%bx", &Data);
XBYTE[Add] = Data;
}
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