I have the follwing problem? I have just three files in my project. 1. main.c 2.I2c_sw.c 3.Startup.a51 I2c_sw.c file has few lines of assembly code. so I have checked "Generate Assmebler SRC File" & "Assemble SRC File" Options It worked fine. But If I were set the above options to main.c file the follwing error occured. *** WARNING L1: UNRESOLVED EXTERNAL SYMBOL SYMBOL: ?C_START MODULE: Startup.obj (?C_STARTUP) *** WARNING L2: REFERENCE MADE TO UNRESOLVED EXTERNAL SYMBOL: ?C_START MODULE: Startup.obj (?C_STARTUP) ADDRESS: 00A2H I am not able to find C_START function/ any such lable? And how "LJMP ?C_START" instruction in STARTUP.A51 jumps to main(). Kindly explain me the programme excution sequence clearly and how to clear the above error, more importantly why it happend?
Hello. It is a very common problem, as we all face it in the begining. (I mean when we try to use assembly in keil C.)Just include the C51S.lib file in your project. also go thru this. http://www.keil.com/support/docs/1646.htm And thru this http://www.keil.com/forum/docs/thread5673.asp And say thanks to Jon Ward.
"...It worked fine. But If I were set the above options to main.c file the follwing error occured." So don't do that, then!
Thank you Sarang Patki. I got it.