/*INTEL 82355 MCR emulation This chip was used as part of many 386 chipsets It controls memory addressing and shadowing*/ #include #include #include #include #include "86box.h" #include "cpu/cpu.h" #include "mem.h" int nextreg6; uint8_t mcr22; int mcrlock,mcrfirst; void resetmcr(void) { mcrlock=0; mcrfirst=1; shadowbios=0; } void writemcr(uint16_t addr, uint8_t val) { pclog("MCR: write %04X %02X %04X:%04X\n",addr,val,CS,cpu_state.pc); switch (addr) { case 0x22: if (val==6 && mcr22==6) nextreg6=1; else nextreg6=0; break; case 0x23: if (nextreg6) shadowbios=!val; break; } mcr22=val; }