use memory macros, fix serial PIT counter, fix mouse button flags (T.Yui)
USE_EGCASM equ 1 EARG1 equ 4 EARG2 equ (EARG1+4) EARG3 equ (EARG2+4) EARG4 equ (EARG3+4) FC_ARG3 equ 4 FC_ARG4 equ (FC_ARG3+4) FC_ARG5 equ (FC_ARG4+4) FC_ARG6 equ (FC_ARG5+4)