Hello,

I'm using AT89C51ED2 Controller and Keil Compiler. I'm confused about the CKSEL, OSCCON and CKRL SFRs which are listed in H-File. CKSEL and OSCCON are not described in datasheet, and CKRL is poorly described. Can anyone tell me the exact function of these SFRs including single Bit Function? Where can I get these informations?

Thanks,

Ralf