my first Q is, while simulating in KEIL does it not able to read the SBUF. when i am simulating the program and i make RI high then it goes to the intrupet and then put SBUF= any value like SBUF='s' and then the cursor goes to my reading line i.e var=SBUF; but after this there is no value in var and one more thing if the var has some value before var=SBUF; it goes zero all gone . so now i am doubting keil simulator. but my transmit part is working fine.