i have read Mark Odell's UART driver. However,the code size is too large for me. can i just using the simple function call: char x,y; getchar(y); //get char from urat x=y; putchar(x); //put char to urat is it possible to do that in keil?
Of course it is - it will use Keil's Library implementations of putchar and getchar. But it won't be interrupt driven, and only supports the "standard" 8051 UART. Keil also have an interrupt-driven example in the downloads section - I dunno if it's any more compat than Mark's.
...not that Mark's driver looks like bloatware to me anyway!