Hi! i am using P89c669 as master and P89v51 as Slave.The Slave program it self by using IAP method.the hex file for the program is received form master.so the master have the hex file.now the problem is to convert the normal hex to prefix added hex value [0x].because keil is not support the hex values without 0x prefix.Is there any solution for this. Thanks & Regards, K.T.Venkatesh.