| III.9 Predefined Symbols For easy access to the 8051 special function register and interrupt addresses, ASEM-51 has a number of predefined (built-in) DATA, BIT and CODE symbols. These predefined symbols can be switched off with the $NOMOD51 control. For detailed information on symbols and addresses refer to Appendix C. For identification of the assembler and its version number, the following NUMBER type symbols are predefined: ??ASEM_51 = 8051H ASEM-51 ??VERSION = 0130H version 1.3 These two symbols can not be switched off!