; This file is an assembly listing that provides the offsets for some ; variables used by the PC's BIOS biosvars segment at 40h ; COM port base addresses. The following four words provide the ; base I/O addresses of COM1: through COM4: com1Base word ? com2Base word ? com3Base word ? com4Base word ? ; LPT base addresses. The following four word provide the base addresses ; for up to four printer ports. lpt1Base word ? lpt2Base word ? lpt3Base word ? lpr4Base word ? ; The following word contains the installed hardware flag. This is somewhat ; obsolete on new machines. InstalledHW word ? ; The following location is not used by most BIOSes. byte ? MemorySize dword ? ; The following bytes contain status information about the keyboard. KbdFlags1 byte ? ;Shift/ctrl/alt/etc. KbdFlags2 byte ? AltKpdEntry byte ? HeadPtr word ? TailPtr word ? TypeAhead word ? FloppyRecal byte ? FloppyMotor byte ? MotorOffCntr byte ? FloppyPrevSt byte ? FloppyCtrlrSt byte ? DisplayMode byte ? NumberColumns word ? RegenBufLen word ? RegenBufAdrs word ? CursorPosn word 8 dup (?) CursorType word ? CurDispPage byte ? VideoAdrs word ? Cur3x8Setting byte ? Cur3x9Setting byte ? ResetAdrs dword ? byte ? Timer dword ? TimerOverflw byte ? BrkKeyState byte ? ResetFlag word ? HardDiskStat byte ? HardDiskNum byte ? HardDiskCtrl byte ? HardDiskCtrlr byte ? lpt1TimeOut byte ? lpt2TimeOut byte ? lpt3TimeOut byte ? lpt4TimeOut byte ? Com1TimeOut byte ? Com2TimeOut byte ? Com3TimeOut byte ? Com4TimeOut byte ? KbdBufStart word ? KbdBufEnd word ? VideoRows byte ? CharHeight byte ? VideoState1 byte ? VideoState2 byte ? word ? MediaControl byte ? HardDiskCStat byte ? HardDiskErr byte ? HardDiskInt byte ? Drv0MediaState byte ? Drv1MediaState byte ? word ? Drv0CurTrk byte ? Drv1CurTrk byte ? KbdModeFlags byte ? KbdLEDFlags byte ? UserWaitAdrs dword ? UserWaitCnt dword ? WaitActiveFlg byte ? byte 7 dup (?) VideoParms dword ? EGASaveArea dword ? AlphaCharGen dword ? GraphCharGen dword ? SecndarySavePtr dword ? byte 68 dup (?) PrtScStatus byte ? biosvars ends end