equ.8

PC x386 bios source code

	;
	; BIOS equates
	;
	; (C)1997-2001 Pascal Dornier / PC Engines; All rights reserved.
	; This file is licensed pursuant to the COMMON PUBLIC LICENSE 0.5.
	;

	;
	; System board I/O ports
	;
dma0	equ	00h	;Primary 8237 DMA controller
pic0	equ	20h	;primary 8259 interrupt controller
timer	equ	40h	;8254 timer

#if ! def	port61
port61	equ	61h	;miscellaneous control
#endif

kb_dat	equ	60h	;keyboard data port
kb_stat	equ	64h	;keyboard status / command port
cm_idx	equ	70h	;CMOS index port
cm_dat	equ	71h	;CMOS data port
post	equ	80h	;POST code port
fd_page	equ	81h	;DMA page register 1 (floppy)
port92	equ	92h	;Fast A20 gate / reset
pic1	equ	0a0h	;secondary 8259 interrupt controller
dma1	equ	0c0h	;Secondary 8237 DMA controller
iowait	equ	0ebh	;I/O wait register
npx	equ	0f0h	;x87 coprocessor
hdc	equ	01f0h	;primary hard disk
hdc_dat	equ	hdc	;HD data (16 or 32 bit)
hdc_err	equ	hdc+1	;HD error (read only)
hdc_cnt	equ	hdc+2	;HD sector count
hdc_sec	equ	hdc+3	;HD sector
hdc_cyl	equ	hdc+4	;HD cylinder low
hdc_cyh	equ	hdc+5	;HD cylinder high
hdc_drv	equ	hdc+6	;HD device / head
hdc_cmd	equ	hdc+7	;HD command (write only)
hdc_stat	equ	hdc+7	;HD status (read only)
hdc_stat2	equ	03f6h	;HD alternate status
hdc_ctrl	equ	03f6h	;HD reset, interrupt enable
crtc	equ	03b4h	;CRTC I/O port (monochrome)
crtc_cga	equ	03d4h	;CRTC I/O port (color)
fdc	equ	03f0h	;primary floppy controller
fdc_ctrl	equ	fdc+2	;control register (drive select, motor)
fdc_stat	equ	fdc+4	;FDC status
fdc_data	equ	fdc+5	;FDC data
fdc_rate	equ	fdc+7	;disk rate
fdc_chg	equ	fdc+7	;disk change status (bit 7)
picedge0	equ	04d0h	;primary interrupts edge/level mode
picedge1	equ	04d1h	;secondary interrupts edge/level mode
pci_ad	equ	0cf8h	;PCI address register (32 bit)
pci_dat	equ	0cfch	;PCI data register (32 bit)
			;This is hardwired for $xxfc in
			;several places, look before you
			;change
pci_datl	equ	low(pci_dat)
	;
	; Interrupt vectors
	;
vec00	equ	0
vec08	equ	08h*4	;low hardware interrupts
vec10	equ	10h*4	;BIOS interrupts
vec13	equ	13h*4	;disk interrupt
vec40	equ	40h*4	;vector to floppy interrupt
vec41	equ	41h*4	;vector to drive 80 parameters
vec46	equ	46h*4	;vector to drive 81 parameters
vec70	equ	70h*4	;high hardware interrupts
	;
	; BIOS data area
	;
	; Most BIOSes access this as segment 0040, but I prefer 0000.
	; The only place where this can cause problems is the keyboard
	; buffer, which is offset to segment 0040.
	;
m_fdbase	equ	0078h	;INT1E = disk base

	; we use IRQ area instead of extended BIOS data area for the
	; PS/2 mouse variables. This can be moved anywhere.

#if def	PS2MOUSE
m_msbase	equ	0200h	;base address
m_msvec	equ	m_msbase	;pointer to call-back routine
m_msflag	equ	m_msbase+4	;mouse flags
			;bit 7 = 1: command pending
			;bit 6 = 1: FE request resend
			;bit 5 = 1: FA command acknowledge
			;bit 4 = 1: FC error condition
			;bit 3 = 1: call back installed
			;bit 2 = 1: initialized
			;bit 1..0 : buffer index
m_msbuf	equ	m_msbase+5	;mouse buffer (3 bytes - 1)
m_msend	equ	m_msbase+7
#endif

m_rsio	equ	0400h	;serial I/O ports
m_lpio	equ	0408h	;parallel I/O ports
m_devflg	equ	0410h	;device flags (word)
m_lomem	equ	0413h	;low memory size (word) in 1KB units
m_kbf	equ	0417h	;keyboard flag
m_kbf1	equ	0418h	;keyboard flag 2
m_kbnum	equ	0419h	;Alt-xxx numeric entry
m_kbhead	equ	041ah	;^buffer head
m_kbtail	equ	041ch	;^buffer tail
m_kbbuf	equ	041eh	;keyboard buffer
m_kbbuf9	equ	043eh	;end of keyboard buffer
m_fdrecal	equ	043eh	;floppy recal status
m_fdmot	equ	043fh	;floppy motor status
m_fdcnt	equ	0440h	;floppy motor timer
m_fdstat	equ	0441h	;last floppy status
m_fdfile	equ	0442h	;floppy status / command file
m_vmode	equ	0449h	;video mode
m_vcol	equ	044ah	;video columns (word)
m_vpgsz	equ	044ch	;video page size (word)
m_vpage	equ	044eh	;video page start address (word)
m_vcolrow	equ	0450h	;video column, row (8 pages)
m_vcursor	equ	0460h	;video cursor end, start line (word)
m_vpgno	equ	0462h	;video page number
m_vcrt	equ	0463h	;video CRTC I/O (word)
m_vmsel	equ	0465h	;video mode select register
			;used for key buffer, option CONSOLE
m_vpal	equ	0466h	;video CGA palette register
			;used for serial redirect flag,
			;option CONSOLE.
m_ioofs	equ	0467h	;option ROM offset
m_ioseg	equ	0469h	;option ROM segment
m_timer	equ	046ch	;timer ticks since midnight (4 bytes)
m_timofl	equ	0470h	;1 equ timer overflow
m_brkflg	equ	0471h	;keyboard break flag
m_rstflg	equ	0472h	;reset flag, $1234 if Ctrl-Alt-Del
m_hdstat	equ	0474h	;HDD status last command
m_hdcnt	equ	0475h	;number of HDD drives
m_lptime	equ	0478h	;parallel port time-out (4 bytes)
m_rstime	equ	047ch	;serial port time-out (4 bytes)
m_kbstart	equ	0480h	;^buffer start
m_kbend	equ	0482h	;^buffer end
m_vrow	equ	0484h	;video row count - 1
m_hdst	equ	048ch	;HDD status register
m_hderr	equ	048dh	;HDD error register
m_hdflag	equ	048eh	;HDD interrupt flag
;m_fdinfo	equ	048fh	;floppy info
m_console	equ	048fh	;serial port console flag
m_fdmed0	equ	0490h	;floppy A: media status
;m_fdmed1	equ	0491h	;floppy B: media status
m_conkey	equ	0492h	;console key buffer
;m_fdmed0a equ	0492h	;floppy A: initial media status
;m_fdmed1a equ	0493h	;floppy B: initial media status
m_fdtrk0	equ	0494h	;floppy A: current track
;m_fdtrk1	equ	0495h	;floppy B: current track
m_kbf3	equ	0496h	;keyboard status
m_kbf2	equ	0497h	;keyboard status
m_prtsc	equ	0500h	;print screen status
	;
	; Temporary data area - cleared before boot
	;
tmp_diag	equ	04b0h	;diagnostic hex dump display (16)

tmp_losz	equ	0504h	;low top of memory (32 bit)
tmp_hisz	equ	0508h	;high top of memory (32 bit)
tmp_kbd	equ	0510h	;keyboard response, AA = ok (8)
tmp_kbc	equ	0511h	;keyboard controller, FF = not present
tmp_npx	equ	0514h	;control word, for init
tmp_kbfail equ	0518h	;1 if keyboard failure
tmp_rtc	equ	0519h	;1 if RTC battery failure or bad time /
			;date
tmp_ss	equ	051ah	;RTC second for run check
tmp_mm	equ	051bh	;RTC minute for run check
tmp_timer	equ	051ch	;Timer (16 bit) for timer run check
tmp_tim	equ	051eh	;1 if timer / RTC update failure

tmp_pci	equ	0520h	;workspace for PCI BIOS

tmp_stack	equ	1000h	;POST stack

tmp_buf	equ	1000h	;temporary buffer, used for HDD init
	;
	; RTC / CMOS
	;
cm_nmi	equ	80h	;NMI disable index
cm_ss	equ	0	;RTC seconds
cm_ssa	equ	1	;RTC seconds alarm
cm_mm	equ	2	;RTC minutes
cm_mma	equ	3	;RTC minutes alarm
cm_hh	equ	4	;RTC hours
cm_hha	equ	5	;RTC hours alarm
cm_day	equ	6	;RTC day of week (cleared, not used)
cm_dd	equ	7	;RTC day
cm_mo	equ	8	;RTC month
cm_yy	equ	9	;RTC year
cm_a	equ	0ah	;RTC status, divider
cm_b	equ	0bh	;RTC mode, interrupt control
cm_c	equ	0ch	;RTC interrupt status
cm_d	equ	0dh	;RTC battery status
cm_dia	equ	0eh	;CMOS diagnostic byte (power fail flag)
cm_shut	equ	0fh	;CMOS shutdown register
cm_test	equ	2fh	;CMOS test register (legacy: checksum)
cm_exl	equ	30h	;CMOS extended memory size, low
cm_exh	equ	31h	;CMOS extended memory size, high
cm_cent	equ	32h	;CMOS century
#if def	CM_LEGACY
cm_meml	equ	15h	;CMOS base memory, low
cm_memh	equ	16h	;CMOS base memory, high
cm_exl2	equ	17h	;CMOS extended memory size, low
cm_exh2	equ	18h	;CMOS extended memory size, high
#endif
	;
	; Miscellaneous
	;
eoi	equ	20h	;PIC: End of Interrupt
bofs	equ	0400h	;BIOS segment offset
	;
	; TTY equates
	;
bell	equ	7	;bell
bs	equ	8	;backspace
lf	equ	10	;line feed
cr	equ	13	;carriage return
vidseg	equ	0b000h	;video segment for monochrome
vid_fill	equ	0720h	;fill pattern, space
	;
	; PUSHA stack frame
	;
_ds	equ	18	;pushed before
_es	equ	16	;pushed before
_ax	equ	14
_al	equ	_ax
_ah	equ	_ax+1
_bx	equ	8
_bl	equ	_bx
_bh	equ	_bx+1
_cx	equ	12
_cl	equ	_cx
_ch	equ	_cx+1
_dx	equ	10
_dl	equ	_dx
_dh	equ	_dx+1
_si	equ	2
_di	equ	0
_bp	equ	4
_flags	equ	6
	;
	; RET_SP - subroutine call without stack
	;
ret_sp	macro
	mov	sp,offset >m1	;point to return address
	jmp	#1	;jump to subroutine
m1:	dw	$+2	;return address
#em