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⬅️ Previous capture (2023-01-29)
-=-=-=-=-=-=-
; Tandy 2000 HD 2.00.00 BIOS
; Disassembled and documented by Chuck Coffing <clc@alum.mit.edu>
; Last updated 20120102
; Assemble with nasm: nasm -f bin -o t2k_bios.bin t2k_bios.asm
;
; Tags:
; {TRM} Technical Reference Manual.
; {PR} Programmer's Reference.
; {?} Research question for myself.
; {ODD} Oddity; cruft or bug or unfinished feature?
; {FEAT} Possible new feature.
; {BUG} Probably a bug.
;
; Memory map:
; 0040e {?} segment of indirect area
; 00420 {?} font related
; 00422 Equipment list
; 00424 <<4 to get amount of (reliable) memory
; 00426 0
; 00428 copy of [00424]
; 0042a 0
; 0042c Segment of video buffer
; 00432 System diagnostic failed flags:
; 0x10 bad ROM checksum
; 0x20 bad RAM
; 00442 Boot disk number (0 = FD0, 2 = HD0, ...)
; 00444 Boot offset
; 00446 Boot segment
; 0044a {?} floppy related
; 00472 0
; 00474 Segment of video buffer
; 00476 16 byte table of pointers to character fonts
; 00486 Address Control Register
; 00487 device power-on / reset byte
; 0048a remaining tries to boot from FD; initially 10
; 0048b remaining tries to boot from HD; initially 10
; 00500 Bottom of boot stack
; 00600 Top of boot stack
; 18000 number of 64k banks of detected good memory
; 18002 0
; 18004 2 byte Checksum of 8k ROM; should be 0
; 18006 failing memory: offset of first bad byte
; 18008 failing memory: segment of first bad byte
; 1800a failing memory: stored/expected byte (stored, read both 0 if ok)
; 1800b failing memory: read/actual byte (stored, read both 0 if ok)
; 1800c first canonical segment beyond end of known-good RAM
; 18020 {? 20 bytes of 0}
; 18040 current cursor position
; 18042 current text character attr
; 18043 current fill (scroll) character attr
; 18050 1000; disk related (maybe number of retries, or timeout?)
; 18060 offset where boot sector was placed
; 18062 segment where boot sector was placed
; 18064 offset where boot sector was placed
; 18066 segment where boot sector was placed
; 19000 FD interrupt handler
; 19002 status of last disk op
; 1902c FD param table
; 1903e {?} IO port indirection?
; 19040 {?} IO port indirection?
; 19042 {?} IO port indirection?
; 19044 {?} IO port indirection?
; 19046
; 1a000 modified copy of HDROMImage {?} sum of something (see LFB2)
; 1a002 {?} length of something (see L10f5)
; 1a008
; 1a016
; 1a026 HD0 parameter table
; 1b000 boot sector
; f8000 character generator {TRM 68}
; fe000 - 0xfffff ROM {TRM 68}.
;
; IO ports:
; 0x00 - 0x7f PCS0 {TRM 47}
; 0x02 DMA multiplexer {TRM 49}
; 0x04 terminal count strobe (terminates DMA). FD {TRM 85}
; 0x30 8272 main status register
; 0x60, 62, 70, 72 interrupt controller {TRM 70}
; PCS2 odd bytes: address control register; event bytes: 9007 {TRM 63}
;
; Things to research:
;
; continue at -------
;
; .isWriteChar - logic/comment seems wrong/ is 0x10 write char, or not?
;
;
; finish SetUpHDROM; param table; follow boot sector through
;
; doc meanings/offsets of RecordBootParams
; LFB2
; finish font: line 1075
; messages line 811
; comment line 189- hardware detection
;
; What is ds=0x1a00?
; Seems to be used as an indirect area.
;
; What is at ds=0x1800? system status area?
;
; What is at ds=0x1900? Copy of some portion of BIOS, modified
;
; To verify:
; - High characters (128-255) have same font as low?
;
; Future features:
; - serial boot
; - tool to read revision port of mainboard {TRM 95}
; - tool to read stats of HiRes board {TRM 280}
;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
BITS 16
ORG 0
CPU 186
; CS = 0xfe00
; BP = 0x1f6a or 0x1f7a or 0x1f8a or 0x1f9a
StartOfBoot:
cli ; Disable interrupts during mem test & system diagnostics
; Re-enabled right before PrintMemoryBanner.
cld
jmp short start
nop
; {?} what prints these?
; Note that strings are terminated with 0xff
db 'BOOT ROM version 02.00.00', 0x0d, 0x0a
db 'Copyright 1983,84 Tandy Corp.', 0x0d, 0x0a
db 'All rights reserved.', 0x0d, 0x0a, 0xff
start: ; L56
mov ax, 0x50
mov ss, ax
mov sp, 0x100 ; Stack starts at 0x00600
mov ax, 0x0
mov ds, ax
mov word [0x8], iretInstr ; NMI interrupt vector
mov [0xa], cs ;
;; Set up 8237 DMA controller
mov al, [cs:bp+0x5] ; in release builds, al <- 0x10
mov dx, 0x0
out dx, al ; refresh clock gate on {TRM appendix C}
mov al, 0xb4
mov dx, 0x46
out dx, al ; 8253 PIT Load Mode Word {TRM appendix C}
nop
nop
mov al, 0x1f
mov dx, 0x44
out dx, al ; 8253 PIT Load Counter 2 {TRM appendix C}
nop
nop
mov al, 0x0
mov dx, 0x44
out dx, al ; 8253 PIT Load Counter 2 {TRM appendix C}
nop
nop
;; Detect amount of memory
cld
mov bh, 0xe ; At most 14 banks (=896k) supported. TRM says 784k
; max, but Envision Designs sold a board supporting 896k.
mov bl, 0x0 ; but zero 64k banks detected so far.
mov ax, 0x0
mov ds, ax
mov si, 0x0
.detectAnother64k:
mov ax, 0x5a5a
mov [si], ax ; Write 0x5a5a to ds:0
mov cx, 0x3e8
.delay1:
loop .delay1 ; delay 1000*125ns = 125us
cmp ax, [si] ; Did memory hold 0x5a5a for 125us?
jne .memorySized
not ax ; Invert, and test again, to be sure
mov [si], ax
mov cx, 0x3e8
.delay2:
loop .delay2
cmp ax, [si] ; Did memory hold 0xa5a5?
jne .memorySized
mov ax, ds ; Yes, so...
add ax, 0x1000 ; ...move to next 64k.
mov ds, ax
inc bl ; Note another bank of RAM.
cmp bl, bh ; Have we hit the max supported memory?
jb .detectAnother64k
.memorySized:
cmp bl, 0x2 ; Detected >= 128k?
jae .memoryCorrectlySized
mov bl, 0x2 ; T2K shipped with minimum 128k on mainboard, so assume that.
.memoryCorrectlySized:
mov bh, bl ; Remember # installed 64k banks, in BH
;; Memory test
mov bl, 0x0
mov ax, 0x0
mov ds, ax
mov si, 0xc ; For first bank, do not
mov cx, 0x7ffa ; overwrite first 3 interrupt vectors.
jmp short .setupPattern
.setupNextTest:
mov si, 0x0 ; All other banks get
mov cx, 0x8000 ; completely overwritten.
.setupPattern:
mov dx, 0x5a5a
.loop:
mov [si], dx ; Write 0x5a5a out...
nop ; ...wait...
lodsw ; ...load back into AX...
cmp ax, dx ; ...and verify.
jne .testFailed
inc dl ; Vary test pattern high...
dec dh ; ...and low.
nop
nop
loop .loop
mov ax, ds ; Success; move to next 64k.
add ax, 0x1000
mov ds, ax
inc bl ; Note another good bank of RAM.
cmp bl, bh ; Ran out of banks to test?
jb .setupNextTest ; No; test next.
jmp short .done
.testFailed:
cmp bl, 0x2 ; Failed in first 2 banks?
jae .findBadByte
mov bl, 0x2 ; Oh well... need 128k, so allow and hope.
.findBadByte:
dec si ; Back up to failed word.
mov cl, dh ; DX is expected,
mov ch, ah ; AX is actual.
cmp al, dl ; Was low byte correct?
je .done ; Yes, so high must be bad (SI points, CX compares)
dec si ; Low byte is bad; SI points,
mov cl, dl ; CX compares (CL expected, AL actual).
mov ch, al ;
.done:
mov al, [cs:bp+0x1] ; Hard-coded max # of banks
cmp bl, al
jbe .doneCapped
mov bl, al ; Enforce cap
.doneCapped:
and bl, 0xfe ; Clear low bit (upgrades come in 128k, so fail in 128k chunks)
mov bh, 0x0 ; No longer care about # physical banks.
mov di, bx ; DI is final # banks of good RAM (>=2)
;; some hardware init
mov ax, [cs:bp+di+0x2] ; Get byte for ACR and device reset
mov dx, 0x101
out dx, al ; Address Control Register {TRM appendix C, 280}
mov al, ah
mov dx, 0x0
out dx, al ; Power up / reset devices
;; Save memory diags, etc
mov dx, ds
mov ax, 0x1800
mov ds, ax
mov ax, 0x0
mov es, ax
mov al, [cs:bp+0x0] ; Index of hardware profile; usually 3
mov [es:0x420], al ; Save hardware profile index for later; configures fonts
mov bh, 0x0 ; {ODD BH is already 0}
mov [0x0], bx ; [0x18000] <- # good 64k banks
mov di, bx ; {ODD DI is already # good banks}
mov ax, [cs:bp+di+0x2] ; Get byte for ACR again
mov [es:0x486], al ; Address Control Register
mov [es:0x487], ah
mov word [es:0x432], 0x0 ; System diagnostic defaults to good.
mov [0x6], si ; Offset of byte of bad memory
mov [0x8], dx ; Segment of byte of bad memory
mov [0xa], cl ; stored/expected byte (no bad mem? cl=ch=0)
mov [0xb], ch ; read/actual byte (no bad mem? cl=ch=0)
mov ax, si
shr ax, 0x4
add ax, dx
mov [0xc], ax ; Canonical segment of first address beyond known-good RAM
cmp ax, 0x2000
jae .enoughGoodRam
mov ax, 0x2000
jmp short .badRam
.enoughGoodRam:
test ax, 0x1fff
jz .multipleOf128KOk
and ax, 0xe000 ; Round down to prior multiple of 128k
jmp short .badRam
.multipleOf128KOk:
cmp si, byte +0x0 ; {BUG si==0 is not the most correct test of all mem good}
jz .goodRam
.badRam:
or word [es:0x432], 0x20 ; Fail system diagnostic due to bad RAM in lowest 128k
.goodRam:
mov [es:0x424], ax ; Amount of (reliable) memory (>>4)
mov word [es:0x426], 0x0
mov [es:0x428], ax
sub ax, 0x140 ; -5k
mov word [es:0x472], 0x0 ;
mov [es:0x474], ax ; Video segment buffer
mov word [es:0x42a], 0x0
mov [es:0x42c], ax
;; Checksum the ROM
mov si, 0x0
mov cx, 0x1000
xor ax, ax
.loopChecksum:
add al, [cs:si]
inc si
add ah, [cs:si]
inc si
loop .loopChecksum
mov [0x4], ax ; [0x18004] = checksum of all 8k of ROM
or ax, ax
jz .finishedRomChecksum ; {? is there a byte somewhere to compensate, to make it 0?}
or word [es:0x432], 0x10 ; Fail system diagnostic due to nonzero checksum of ROM
.finishedRomChecksum:
;; Detect hi-res board
mov ax, 0x0
mov ds, ax
mov dx, 0x180
in al, dx ; Hi-res board status {TRM 281}
mov cl, 0x28 ; Default equipment list: {PR 233}
mov ch, 0x21 ; FD1, reserved, BW monitor, joysticks
cmp al, 0xff ; No response on this IO port?
je .doneDetectingHiRes
test al, 0x1 ; have HiRes board? (0=yes)
jz .configHiResPalette
or cl, 0x1 ; no HiRes: monochrome graphics option {PR 233}
or ch, 0x4 ; reserved {PR 233}
jmp short .doneDetectingHiRes
.configHiResPalette:
push ax ; See {TRM 280}
mov dx, 0x198 ; low-intensity background:
mov al, 0x0 ; black
out dx, al
mov dx, 0x19a ; low-intensity character:
mov al, 0xf ; white
out dx, al
mov dx, 0x19c ; hi-intensity background:
mov al, 0x0 ; black
out dx, al
mov dx, 0x19e ; hi-intensity character:
mov al, 0x7 ; white
out dx, al
pop ax
test al, 0x20 ; HiRes status bit: "future use" {TRM 281}
jnz .hiResFutureBit
test al, 0x2 ; HiRes status bit:
jnz .plane0Only ; 3 planes installed?
or cl, 0x2 ; monochrome graphics option {PR 233} {ODD}
jmp short .doneProbingHiRes
.plane0Only:
or cl, 0x4 ; mono with color option {PR 233}
jmp short .doneProbingHiRes
.hiResFutureBit:
or cl, 0x6 ; mono + mono with color {PR 233}
.doneProbingHiRes:
or ch, 0x2 ; color {PR 233}
.doneDetectingHiRes:
mov [0x422], cx ; Set equipment list
;; Default all remaining interrupts to be ignored
mov ax, cs
mov ds, ax
mov ax, 0x0
mov es, ax
cld
mov di, 0xc ; First 3 are already set.
mov cx, 0xfd
.setDefaultIntHandlers:
mov ax, iretInstr
stosw
mov ax, 0xfe00
stosw
loop .setDefaultIntHandlers
;; Patch up interrupts from patch table
mov si, IntPatchTable
nop
.patchInts:
lodsw ; Load offset to change in IDT
cmp ax, 0xffff
jz .donePatchingInts
mov di, ax
movsw ; Patch IDT with offset of handler
jmp short .patchInts
.donePatchingInts:
;; Init some hardware
mov ax, cs
mov ds, ax
mov si, ProgramFoo1
nop
call OutPorts
mov si, ProgramFoo2
nop
call OutPorts
mov si, ProgramFoo3
nop
call OutPorts
;; Load character fonts
mov ax, cs
mov es, ax
mov bx, CharSet8x8 ; 128 chars * 8x8 cells = 1024 = 0x400 bytes
nop
mov al, 0x1 ; Set char font, for 0-127 8x8
mov ah, 0x10 ; Get/set char font
int 82 ; Video interrupt
mov bx, CharSet8x8
nop
mov al, 0x3 ; Set char font, for 128-255 8x8
mov ah, 0x10 ; Get/set char font
int 82 ; Video interrupt
mov bx, CharSet8x16 ; 128 chars * 8x16 cells = 2048 = 0x800 bytes
nop
mov al, 0x5 ; Set char font, for 0-127 8x16
mov ah, 0x10 ; Get/set char font
int 82 ; Video interrupt
mov bx, CharSet8x16
nop
mov al, 0x7 ; Set char font, for 128-255 8x16
mov ah, 0x10 ; Get/set char font
int 82 ; Video interrupt
;; Clear screen
mov ax, 0x1800
mov ds, ax
mov bl, 0xa ; foreground color
call PrintFormFeed
;; Program the video card
mov ax, cs
mov ds, ax
mov si, Program9007
nop
call OutPorts
;;
cld
mov ax, cs
mov ds, ax ; {ODD useless to set DS for stosw; DS also set below}
mov ax, 0x1800
mov es, ax
mov ax, 0x0
mov di, 0x20
mov cx, 0xa ; Zero out ten words:
rep stosw ; memset(0x18020, 0, 20)
;;
sti
call PrintMemoryBanner
;;
call Delay ; {? Probably gives HD more time to spin up}
mov ax, 0x1800
mov ds, ax
mov ax, 0x0
mov es, ax
mov word [0x2], 0x0 ; [18002] <- 0x0
mov byte [es:0x48a], 0xa ; 10 retries to read from FD at boot
mov byte [es:0x48b], 0xa ; 10 retries to read from HD at boot
push ds
push es
call BootFromFD
pop es
pop ds
jc .fdFailedTryHd
mov al, 0x0 ; booted from FD0
call .goodBoot
.fdFailedTryHd:
push ds
push es
call BootFromHD
pop es
pop ds
jc .hang
mov al, 0x2 ; booted from HD0
call .goodBoot
.hang: ; {FEAT print failure to explain hang}
jmp short .hang
.goodBoot:
push ds
push es
mov [es:0x442], al ; Note FD vs HD boot
mov ax, [0x64] ; Get offset of boot sector
mov [es:0x444], ax ; ...save to standard BIOS area.
mov ax, [0x66] ; Get segment of boot sector (0x1b00)
mov [es:0x446], ax ; ...save to standard BIOS area.
mov es, ax
call far [0x64] ; Call bootsector. Will hang if it returns.
pop es ; {FEAT print failure to explain hang}
pop ds
ret
errRet: ; L331
jmp short stcAndRet ; {ODD What's the point of this?}
stcAndRet: ; L333
stc
jmp short andRet
clcAndRet: ; L336
clc
andRet:
ret
; Note: DS = 0x1800
RecordBootParams:
mov [0x50], cx ; {ODD nothing uses this?}
mov [0x52], cx ; {ODD nothing uses this?}
mov word [0x64], 0x0 ; Offset of boot sector
mov word [0x66], 0x1b00 ; Segment of boot sector
mov word [0x60], 0x0 ; Offset of boot sector {ODD BootFromFD sets 60 but .goodBoot reads 64}
mov word [0x62], 0x1b00 ; Segment of boot sector
ret
BootFromFD: ; L359
mov cx, 0x3e8 ; {ODD stuffed into [0x50] but not used}
call RecordBootParams
call SetUpFDROM
.retry:
mov dl, 0x0 ; use FD not HD
mov ah, 0x0 ; Reset floppy disk
int 86 ; Int86FDHD
or ah, ah
jnz .checkError
mov dh, 0x0 ; head 0
mov dl, 0x0 ; use FD not HD; FD#0
mov ch, 0x0 ; cylinder 0
mov cl, 0x1 ; sector 1
mov al, 0x1 ; 1 sector
les bx, [0x60] ; Where to put data
mov ah, 0x2 ; Read sector(s) from floppy disk
int 86 ; Int86FDHD
or ah, ah ; read ok?
jz .ok
dec byte [es:0x48a] ; consumed a retry
jnz .retry
jmp short .badRead
nop
.ok:
cmp al, 0x1 ; read the 1 sector requested?
jnz .badRead
jmp short clcAndRet
.checkError:
test ah, 0x7f
jnz .badRead ; ok?
jmp short stcAndRet ; error!
.badRead:
jmp short errRet
BootFromHD: ; L39B
mov cx, 0x3e8 ; {ODD stuffed into [0x50] but not used}
call RecordBootParams
call SetUpHDROM
.retry:
mov dl, 0x80 ; use HD not FD
mov ah, 0x0 ; Reset
int 86 ; Int86FDHD
or ah, ah
jnz .fail
mov dh, 0x0 ; head 0
mov dl, 0x80 ; use HD not FD
mov ch, 0x0 ; cylinder 0
mov cl, 0x1 ; sector 1
mov al, 0x1 ; read 1 sector
les bx, [0x60] ; Where to put data
mov ah, 0x2 ; Read sector(s)
int 86 ; Int86FDHD
or ah, ah
jz .ok
dec byte [es:0x48b] ; consumed a retry
jnz .retry
jmp short .fail
nop
.ok:
cmp al, 0x1 ; Expect al == 1, or...
jnz .fail ; error!
jmp clcAndRet ; success
jmp stcAndRet ; {ODD how can anything get here?} error!
.fail:
jmp errRet
iretInstr: ; L3DB
iret
;; Common interrupt handling routines; see patch table at L82C
;L3DC: ; {? unused?}
push ax
mov ax, 0x1
jmp short L3FE
Int0DivideError: ; L3E2
push ax
mov ax, 0x2
jmp short L3FE
IntSystemTimer: ; L3E8
push ax
mov ax, 0x4
jmp short L3FE
L3EE: ; {? unused?}
push ax
mov ax, 0x8
jmp short L3FE
L3F4:
push ax
mov ax, 0x40
jmp short L3FE
L3FA:
push ax
mov ax, 0x80
L3FE:
push ds
push bx
mov bx, 0x0
mov ds, bx
or [0x432], ax ; {? setting system diagnostic flag, because
; unexpected int during boot?}
pop bx
pop ds
pop ax
iret
;-----------
sti
push ds
pusha
call L487
popa
pop ds
iret
sti
push ds
pusha
call L48E
popa
pop ds
iret
sti
push ds
pusha
mov si, 0x20
call L474
jz L42A
L42A:
call L49F
popa
pop ds
iret
sti
push ds
pusha
mov si, 0x28
call L474
jz L43B
L43B:
call L487
popa
pop ds
iret
Int118: ; L441
sti
push ds
pusha
mov si, 0x2c
call L474
jz L44C
L44C:
call L487
popa
pop ds
iret
Int120: ; L452
sti
push ds
pusha
mov si, 0x30
call L474
jz L45D
L45D:
call L48E
popa
pop ds
iret
Int121: ; L463
sti
push ds
pusha
mov si, 0x32
call L474
jz L46E
L46E:
call L48E
popa
pop ds
iret
; {? Seems like this is a common handler for ints; si differs}
L474:
mov ax, 0x1800
mov ds, ax
mov ax, 0xffff
jmp short .L481
mov ax, 0x0
.L481:
nop
nop
nop
or ax, ax
ret
L487:
mov dx, 0x60 ; {TRM appendix C} 8259A-2 write command words
mov al, 0x20
jmp short L493
L48E:
mov dx, 0x70A ; {TRM appendix C} 8259A-2 write command words
mov al, 0x20
L493:
cli
out dx, al ; {TRM appendix C} 8259A-2 write command words
mov al, 0xb
out dx, al ; {TRM appendix C} 8259A-2 write command words
nop
nop
in al, dx
or al, al
jnz L4A7
L49F:
cli
mov dx, 0xff22 ; {? seems like a common way to finish ints?}
mov ax, 0x8000
out dx, ax
L4A7:
sti
ret
Delay: ; L4AC
mov bx, 0x3e8
.top:
call .delay62us ; call 1000 times; ~62+ ms?
dec bx
jnz .top
ret
out dx, al ; {ODD Never executed?}
.delay62us:
mov cx, 0x1f4 ; 500 cycles * 125 nsec = ~62us
.delay:
loop .delay
ret
OutPorts:
lodsb ; load length byte into al
or al, al ; zero length? nevermind.
jz short .done
.one:
dec al
jnz .two
lodsw
mov dx, ax ; dx <- IO port
lodsb ; al <- data for port
out dx, al
jmp short OutPorts
.two:
lodsw
mov dx, ax ; dx <- IO port
lodsw ; ax <- data for port
out dx, ax
jmp short OutPorts
.done:
ret
; length of data, 16-bit IO port, data
ProgramFoo1:
db 0x02, 0x28, 0xFF, 0xC0, 0x00
db 0x02, 0x2A, 0xFF, 0x07, 0x00
db 0x02, 0x38, 0xFF, 0x60, 0x00
db 0x02, 0x3A, 0xFF, 0x65, 0x00
db 0x02, 0x34, 0xFF, 0x02, 0x00
db 0x02, 0x36, 0xFF, 0x03, 0x00
db 0x02, 0x32, 0xFF, 0x07, 0x00
db 0x00
ProgramFoo2:
db 0x01, 0x60, 0x00, 0x13 ; 8259A-2 / write command /
db 0x01, 0x62, 0x00, 0x70
db 0x01, 0x62, 0x00, 0x0D
db 0x01, 0x62, 0x00, 0xEB
db 0x00
ProgramFoo3:
db 0x01, 0x70, 0x00, 0x13 ; 8259A-2 / write command /
db 0x01, 0x72, 0x00, 0x78
db 0x01, 0x72, 0x00, 0x0d
db 0x01, 0x72, 0x00, 0xfc
db 0x00
Program9007:
db 0x01, 0x2c, 0x01, 0x00 ; 9007 / R16 /
db 0x01, 0x2c, 0x01, 0x00 ; 9007 / R16 /
db 0x01, 0x2c, 0x01, 0x00 ; 9007 / R16 /
db 0x01, 0x2c, 0x01, 0x00 ; 9007 / R16 /
db 0x01, 0x00, 0x01, 0x6a ; 9007 / R00 /
db 0x01, 0x02, 0x01, 0x4f
db 0x01, 0x04, 0x01, 0x10
db 0x01, 0x06, 0x01, 0x08
db 0x01, 0x08, 0x01, 0x08
db 0x01, 0x0a, 0x01, 0x21
db 0x01, 0x0c, 0x01, 0x52
db 0x01, 0x0e, 0x01, 0x18
db 0x01, 0x10, 0x01, 0x2f
db 0x01, 0x12, 0x01, 0xb8
db 0x01, 0x14, 0x01, 0x6a
db 0x01, 0x16, 0x01, 0x02
db 0x01, 0x18, 0x01, 0x00
db 0x01, 0x1a, 0x01, 0x36
db 0x01, 0x1c, 0x01, 0x00
db 0x01, 0x1e, 0x01, 0x00
db 0x01, 0x20, 0x01, 0xfe
db 0x01, 0x22, 0x01, 0xfe
db 0x01, 0x24, 0x01, 0xfe
db 0x01, 0x26, 0x01, 0x00
db 0x01, 0x28, 0x01, 0x00
db 0x01, 0x2e, 0x01, 0x00
db 0x01, 0x30, 0x01, 0x00
db 0x01, 0x32, 0x01, 0x00
db 0x01, 0x34, 0x01, 0x00
db 0x01, 0x2a, 0x01, 0x00
db 0x01, 0x2a, 0x01, 0x00
db 0x01, 0x2a, 0x01, 0x00
db 0x01, 0x2a, 0x01, 0x00
db 0x00
PrintMemoryBanner:
push ds
push es
mov ax, 0x1800
mov ds, ax
mov ax, 0x0
mov es, ax
mov ax, [es:0x432] ; Get system diagnostic (0 is good)
or ax, ax
jnz .badDiag
mov bl, 0xa ; light green
call PrintEmptyChar
mov si, sMemorySize
nop
call PrintString
mov si, [0x0] ; 0x18000 number 64k banks detected good
sub si, byte +0x2
add si, si
add si, s128k
call PrintString ; Print memory size
mov si, sKilobyteLabel
nop
call PrintString
call PrintCRLFBeep
jmp short .done
.badDiag:
mov bl, 0xa ; light green
call PrintEmptyChar
mov si, sSystemFailsDiag
nop
call PrintString
call PrintCRLFBeep
.lockup:
jmp short .lockup
.done:
pop es
pop ds
ret
PrintCRLFBeep:
mov bl, 0xa ; light green
call PrintEmptyChar
mov si, sCRLF
nop
jmp short PrintString
mov si, sBeep
nop
jmp short PrintString
; {ODD How to get here?}
mov si, s2Spaces
nop
PrintString: ; L602
push ax
push bx
mov bl, 0xf ; Foreground color white
.nextChar:
mov al, [cs:si]
inc si
cmp al, 0xff ; string terminator?
jz .endOfString
call PrintChar
jmp short .nextChar
.endOfString:
pop bx
pop ax
ret
PrintEmptyChar: ; L616
push ax
mov al, 0x0 ; {ODD Why print ascii 0 vs space?}
call PrintChar
pop ax
ret
PrintFormFeed: ; L61E
mov al, 0xc ; formfeed
PrintChar: ; L620
push ax
mov ah, 0xe ; Write TTY
int 82 ; Video interrupt
pop ax
ret
; {? how to get here?}
mov al, bh
call .L62E
mov al, bl
.L62E:
push ax
shr al, 0x4
call .L636
pop ax
.L636:
and al, 0xf
cmp al, 0xa
jc .L63E
add al, 0x7
.L63E:
add al, 0x30
push bx
mov bl, 0xf
call PrintChar
pop bx
ret
sCRLF: ; L648
db 0x0d, 0x0a, 0xff
sBeep:
db 0x07, 0xff
s2Spaces:
db 0x20, 0x20, 0xff
sMemorySize: ; L650
db 'Memory Size = ', 0xff
s128k:
db '128', 0xff
db '256', 0xff
db '384', 0xff
db '512', 0xff
db '640', 0xff
db '768', 0xff
; {FEAT} Support 896k, as offered by the Evince board
sKilobyteLabel:
db 'K', 0xff
sSystemFailsDiag: ; L679
db 'System Fails Diagnostic Test', 0xff
; ax = 0xe
; bl foreground color
Int82Video: ; L696
push ds
push es
pusha
mov bp, sp
cmp ah, 0xe ; Write TTY?
jne .isWriteChar
call .writeTTY
jmp short .done
.isWriteChar:
cmp ah, 0x10 ; Write Character?
jne .done
call GetSetCharFont
.done:
popa
pop es
pop ds
iret
.writeTTY:
mov cx, 0x0
mov ds, cx
mov es, [0x474] ; get video buffer segment
mov cx, 0x1800
mov ds, cx
mov ah, bl ; bl = foreground color
and ah, 0xf
cmp ah, 0xa
jne .notFormFeed
mov [0x42], bl ; save color
cmp al, 0xc ; is form feed?
jnz .notFormFeed
mov [0x43], bl ; save fill color
.notFormFeed: ; L6D5
mov ah, [0x42] ; get color
mov bx, [0x40] ; get cursor position
cmp al, 0x20
jnc .writeSpace
cmp al, 0x7
je .writeBell
cmp al, 0x8
je .writeBackspace
cmp al, 0x9
je .writeTab
cmp al, 0xa
je .writeLineFeed
cmp al, 0xc
je .writeFormFeed
cmp al, 0xd
je .writeCarriageReturn
.L6F9:
jmp short .ret
nop
.writeSpace:
call CalcRowColOffsetDi
stosw
inc bl
jmp short .doneWriting
.writeBell:
call Bell
jmp short .L6F9
.writeBackspace:
cmp bl, 0x0
jz .L6F9
dec bl
jmp short .doneWriting
.writeTab:
add bl, 0x8
and bl, 0xf8
jmp short .doneWriting
.writeLineFeed:
inc bh
jmp short .doneWriting
.writeFormFeed:
mov bx, 0x0
call CalcRowColOffsetDi
mov cx, 0x7d0 ; 25 rows * 80 cols
mov al, 0x20 ; space
mov ah, [0x43] ; get fill color
rep stosw
jmp short .doneWriting
.writeCarriageReturn:
mov bl, 0x0
.doneWriting:
call CheckWrap
mov [0x40], bx ; save new cursor position
mov al, bh
mov dx, 0x130
out dx, al ; {TRM appendix C} 9007 R18
mov al, bl
mov dx, 0x132 ; {TRM appendix C} 9007 R19
out dx, al
.ret: ; L746
ret
CalcRowColOffsetDi: ; L747
push ax
push bx
mov di, 0x0
mov al, 0x50
mul bh ; ax = row *= 80
mov bh, 0x0
add ax, bx ; add column offset
add ax, ax ; double due to character attrs
add di, ax
pop bx
pop ax
ret
CheckWrap: ; L75B
cmp bl, 0x50 ; Hit the 80th column?
jc .checkRow
mov bl, 0x0 ; Yes, back to 0 column,
inc bh ; and down a line.
.checkRow:
cmp bh, 0x19 ; Hit the 25th row?
jc .noScroll
mov bh, 0x18 ; Yes, but stay where you are;
call ScrollScreenUp ; and scroll.
.noScroll:
ret
ScrollScreenUp:
push ds
push bx
push es
pop ds
mov bl, 0x0
mov bh, 0x1
call CalcRowColOffsetDi
mov si, di ; offset of 1, 0
mov bh, 0x0
call CalcRowColOffsetDi
mov cx, 0x780 ; 24*80*2
rep movsw ; Copy from 1,0 to 0,0
mov cx, 0x50
mov al, 0x20
mov ah, [0x43] ; get fill color
rep stosw ; fill last line
pop bx
pop ds
ret
Bell:
; {FEAT: umm... perhaps beep?}
ret
; If setting, ES:BX points to character font
; If getting, ES:BX is set to current character font
; al bit 0: setting?
; al bits 1,2: which set
GetSetCharFont: ; L795
mov cx, 0x0
mov ds, cx
mov si, 0x476
push ax
and ax, 0x6
add ax, ax
add si, ax ; 0x476: 0-127 8x8, 0x47a: 128-255 8x8, 0x47c: 0-127 8x16, 0x480: 128-255 8x16
pop ax
test al, 0x1 ; Change pointer to new character set?
jnz .writePointerToChar
mov bx, [si]
mov es, [si+0x2] ; es:bx now points to character font
mov [bp+0x8], bx
mov [bp+0x10], es
jmp short .out
nop
.writePointerToChar: ; L7B8
mov [si], bx
mov [si+0x2], es ; save caller's es:bs pointer to character font
test al, 0x4 ; 8x16 cell?
jnz .is8x8Font
jmp short .out
nop
.is8x8Font: ; L7C4
mov ah, [0x420] ; {?} video feature flags? determines where to put font
mov si, bx
mov bx, es
mov ds, bx
mov bx, 0xf800 ; ROM for fonts
mov es, bx
mov di, 0x0
mov cx, 0x800
cmp ah, 0x1
ja .L7E0
jz .L7EF
.L7E0:
test al, 0x2
jz .L7E8
add di, 0x1000
.L7E8:
movsb
inc di
loop .L7E8
jmp short .out
nop
.L7EF:
test al, 0x2
jz .L7F7
add di, 0x2000
.L7F7:
push cx
lodsb
xor dl, dl
mov cx, 0x8
.L7FE:
shr al, 1
adc dl, dl
loop .L7FE
mov ax, di
and ax, 0x3c
shr ax, 0x2
xor bx, bx
mov cx, 0x4
.L811:
shr ax, 1
adc bx, bx
loop .L811
shl bx, 0x2
mov ax, di
and ax, 0xffc3
or bx, ax
mov [es:bx], dl
pop cx
add di, byte +0x4
loop .L7F7
.out:
ret
; {? Seems unused}
iret
;; Patch table to fix up interrupt handling:
;; Words are alternating offset of IDT and offset of call in ROM
IntPatchTable: ; L82C:
db 0x00, 0x00, 0xe2, 0x03 ; 0: divide error L3E2
db 0x04, 0x00, 0xe2, 0x03 ; 1: single step L3E2
db 0x08, 0x00, 0xdb, 0x03 ; 2: NMI: iret L3DB
db 0x0c, 0x00, 0xe2, 0x03 ; 3: breakpoint L3E2
db 0x10, 0x00, 0xe2, 0x03 ; 4: overflow L3E2
db 0x14, 0x00, 0xE2, 0x03 ; 5: print screen L3E2
db 0x18, 0x00, 0xE2, 0x03 ; 6: invalid op code L3E2
db 0x1C, 0x00, 0xE2, 0x03 ; 7: processor extention not available L3E2
db 0x28, 0x00, 0x49, 0x0D ; 9: hard disk? (or lpt2? vertical retrace?) LD49
db 0x2C, 0x00, 0x5E, 0x0D ; 10: COM2 LD5E
db 0x20, 0x00, 0xE8, 0x03 ; 8: system timer L3E8
db 0x48, 0x00, 0xE8, 0x03 ; 18: Memory size {PR 234} L3E8
db 0x4C, 0x00, 0xE8, 0x03 ; 19:
db 0xC8, 0x01, 0xE8, 0x03 ; 114:
db 0xCC, 0x01, 0xE8, 0x03 ; 115:
db 0xD0, 0x01, 0x16, 0x0C ; 116:
db 0xD4, 0x01, 0x16, 0x0C ; 117:
db 0xD8, 0x01, 0x41, 0x04 ; 118:
db 0xDC, 0x01, 0xE8, 0x03 ; 119:
db 0xE0, 0x01, 0x52, 0x04 ; 120:
db 0xE4, 0x01, 0x63, 0x04 ; 121:
db 0xE8, 0x01, 0xE8, 0x03 ; 122:
db 0xEC, 0x01, 0xE8, 0x03 ; 123:
db 0x48, 0x01, 0x96, 0x06 ; 82: video display Int82Video L696
db 0x40, 0x00, 0x96, 0x06 ; 16: video display Int82Video L696
db 0x58, 0x01, 0x1B, 0x09 ; 86: floppy disk {PR 194} Int86FDHD L91B
db 0x4C, 0x00, 0x1B, 0x09 ; 19: floppy and hard disk {PR 194} Int86FDHD L91B
db 0xFF, 0xFF ; marker for end of patch table
SetUpFDROM: ; L89D
pusha
push ds
mov ax, 0x1900 ; write to disk area...
mov es, ax
mov ax, 0xfe00 ; ...from ROM.
mov ds, ax
mov si, FDIntHandler
nop
mov di, 0x0
mov cx, 0x48 ; Copy int handler and param table.
nop
cld
rep movsb ; Do the copy.
mov ax, 0x0
mov ds, ax
mov word [0x78], 0x2c ; int 1e: Update floppy disk parameter pointer {PR 194}
mov word [0x7a], 0x1900
mov al, 0x0
out 0x2, al ; DMA control port: disable all {TRM appendix C}
mov [0x44a], al ;
mov [es:0x46], al
pop ds
popa
ret
FDIntHandler: ; L8D3
db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x04, 0x00, 0x00
db 0x00, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x66, 0xa2, 0x00, 0x00, 0x04
db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x80, 0x00, 0x00, 0x00, 0x00, 0x00, 0x86, 0x16
FDParamTable: ; {Ralf Brown, Int 1E, Table 0929}
db 0xe0, 0x8c, 0x00, 0x02, 0x09, 0x2a, 0xff, 0x50, 0xf6, 0x19, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00
db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
; dl: FD or HD
; ah: command
Int86FDHD: ; L91B
sti
push ds
push es
push bx
push cx
push ds
push si
push di
push bp
push dx
mov bp, sp
mov si, 0x1900
mov ds, si
call .doDiskOp
mov ah, [0x2] ; Get status of last disk op
cmp ah, 0x1
cmc ; carry flag implies failure {PR 220}
pop dx
pop bp
pop di
pop si
pop ds
pop cx
pop bx
pop es
pop ds
retf 0x2
.doDiskOp:
mov dh, al
or ah, ah
jz .resetDisks
cmp ah, 0x1
jz .getLastDiskOpStatus
mov byte [0x2], 0x0 ; Assume disk op will be successful
cmp dl, 0x2
jnc .readSectorsFromHD ; {?} what is dl?
cmp ah, 0x2
jnz .readSectorsFromHD
jmp otherDiskOps
.readSectorsFromHD:
mov byte [0x2], 0x1 ; status of last disk op: Bad command
ret
.getLastDiskOpStatus:
mov al, [0x2]
ret
.resetDisks:
push ds
mov ax, 0x0
mov ds, ax
mov al, [0x487] ;
pop ds
and al, 0xdf ; mask off Refresh Clock Gate
out 0x0, al ; {TRM appendix C} everything on
mov cx, 0x14
.resetDisksDelay:
loop .resetDisksDelay
or al, 0x20
out 0x0, al ; {TRM appendix C} FDC reset
mov al, 0x5
.L983:
mov cx, 0x0
.resetDisksDelay2:
loop .resetDisksDelay2
dec al
jnz .L983
mov byte [0x2], 0x0 ; last disk op: success
mov cx, 0x3c
.L994:
call LBD8
mov byte [0x0], 0x0
jnc .L9A4
.L99E:
or byte [0x2], 0x20 ; last disk op: CRC error
ret
.L9A4:
mov al, [0x37]
cmp al, 0x80
jz .L9C3
test al, 0x2
jnz .L994
test al, 0x1
jnz .L9BA
xor byte [0x3], 0xff
jmp short .L9BF
.L9BA:
xor byte [0x5], 0xff
.L9BF:
loop .L994
jmp short .L99E
.L9C3:
mov ah, 0x3
call LB08
mov bx, 0x1
call LB36
mov bx, 0x3
call LB36
and byte [0x0], 0xfc
mov dl, 0x0
mov ch, 0xa
call LB4A
jc .LA20
and byte [0x0], 0xfc
mov ch, 0x0
call LB4A
jc .LA20
mov ah, 0x4
call LB08
mov ah, 0x1
call LB08
call LC29
jc .LA20
mov ah, [0x37]
and ah, 0x20
jz .LA17
mov dl, 0x1
mov ch, 0xa
call LB4A
and byte [0x0], 0xfc
mov ch, 0x0
call LB4A
.LA17:
mov dl, 0x0
mov ch, 0x2
call LB4A
jnc .LA26
.LA20:
or byte [0x2], 0x40 ; last disk op: FDC failure
ret
.LA26:
mov ah, 0x4a
call LB08
mov ah, 0x0
call LB08
call LBF4
jnc .LA38
jmp .L99E
.LA38:
call LC29
jnc LA40
jmp .L99E
LA40:
cmp byte [0x3a], 0x2
jz LA4D
mov byte [0x4], 0xff
ret
LA4D:
mov byte [0x4], 0x0
ret
otherDiskOps:
call LBAB
jnc LA60
mov byte [0x2], 0x9 ; {?} last disk op
mov al, 0x0
ret
LA60:
call LB4A
mov dh, 0x0
jc LAB9
push word 0xab9
nop
mov ah, 0x66
call LB08
mov ah, [bp+0x1]
shl ah, 0x2
and ah, 0x4
or ah, dl
call LB08
mov ah, ch
call LB08
mov ah, [bp+0x1]
call LB08
mov ah, cl
call LB08
mov bx, 0x7
call LB36
mov bx, 0x9
call LB36
mov bx, 0xb
call LB36
mov bx, 0xd
call LB36
mov bx, si
pop si
call LCDF
jnc LAB6
or byte [0x2], 0x8 ; last disk op: DMA overrun
jmp short LAFE
nop
LAB6:
call LBF4
LAB9:
jc LAFE
call LC29
jc LAFD
cld
mov si, 0x37
lodsb
and al, 0xc0
jz LB02
cmp al, 0x40
jnz LAF4
lodsb
shl al, 1
mov ah, 0x4
jc LAF6
shl al, 0x2
mov ah, 0x10
jc LAF6
shl al, 1
mov ah, 0x8
jc LAF6
shl al, 0x2
mov ah, 0x4
jc LAF6
shl al, 1
mov ah, 0x3
jc LAF6
shl al, 1
mov ah, 0x2
jc LAF6
LAF4:
mov ah, 0x20
LAF6:
or [0x2], ah ; last disk op:
call LC67
LAFD:
ret
LAFE:
call LC29
ret
LB02:
call LC67
xor ah, ah
ret
; {? FDC writing?}
; Writes ah to floppy
LB08:
push cx
mov cl, 0x20
.delay:
dec cl
jnz .delay ; {? why not loop? why delay at all?}
mov cx, 0x0
.notReadyToWrite:
in al, 0x30 ; Read FDC status {TRM 85}
and al, 0x40 ; I/O direction; 1 = FDC to CPU; 0 = CPU to FDC
jz .readyToWrite
loop .notReadyToWrite
.timeout:
or byte [0x2], 0x80 ; last disk op: timeout error
stc
pop cx
pop ax
ret
.readyToWrite:
mov cx, 0x0
.notReadyForData:
in al, 0x30 ; Read FDC status {TRM 85}
and al, 0x80 ; data ready?
jnz .readyForData
loop .notReadyForData
jmp short .timeout
.readyForData:
mov al, ah
out 0x32, al ; Write to FDC data register {TRM 85}
pop cx
ret
LB36:
push ds
mov ax, 0x0
mov ds, ax
push si
lds si, [0x78] ; Floppy Disk Parameter Pointer {PR 194}
shr bx, 1
mov ah, [bx+si] ; {?} Load ? from a table?
pop si
pop ds
jc LB08
ret
LB4A:
mov al, 0x1
push cx
mov cl, dl
shl al, cl
pop cx
test [0x0], al
jnz LB78
or [0x0], al
mov ah, 0x7
call LB08
mov ah, dl
call LB08
call LBD3
mov ah, 0x7
call LB08
mov ah, dl
call LB08
call LBD3
jc LBAA
LB78:
mov ah, 0xf
call LB08
mov ah, dl
call LB08
mov ah, ch
or byte [0x4], 0x0
jz LB8D
shl ah, 1
LB8D:
call LB08
call LBD3
pushf
mov bx, 0x12
call LB36
push cx
LB9B:
mov cx, 0x226
or ah, ah
jz LBA8
LBA2:
loop LBA2
dec ah
jmp short LB9B
LBA8:
pop cx
popf
LBAA:
ret
LBAB:
mov si, 0x8
mov [si+0xc], es
mov [si+0xa], bx
mov ah, dh
xor al, al
shr ax, 1
push ax
mov bx, 0x6
call LB36
mov bl, ah
pop ax
.LBC4:
shl ax, 1
dec bl
jnz .LBC4
mov bx, si
mov [bx+0xe], ax
call LC7E
ret
LBD3:
call LBF4
jc LBEC
LBD8:
mov ah, 0x8
call LB08
call LC29
jc LBEC
mov al, [0x37]
and al, 0x60
cmp al, 0x60
jz LBED
clc
LBEC:
ret
LBED:
or byte [0x2], 0x40 ; last disk op: seek error
stc
ret
LBF4:
sti
pusha
mov bl, 0xf
xor cx, cx
LBFA:
test byte [0x0], 0x80
jnz LC0D
loop LBFA
dec bl
jnz LBFA
or byte [0x2], 0x80 ; last disk op: timeout error
stc
LC0D:
pushf
and byte [0x0], 0x7f
popf
popa
ret
sti
Int116_117: ; LC16
push ds
pusha
mov ax, 0x1900
mov ds, ax
or byte [0x0], 0x80
call L487
popa
pop ds
iret
; {? FDC reading?}
LC29:
mov di, 0x37
cld
pusha
mov bl, 0x7 ;
LC30:
xor cx, cx ; Retry loop 64k times!
mov dx, 0x30
.loop:
in al, dx ; Read FDC status {TRM 85}
test al, 0x80 ; data ready ready for IO?
jnz DataReady ; ready?
loop .loop
or byte [0x2], 0x80 ; last disk op: timeout error
LC41:
stc
popa
ret
DataReady: ; LC44
in al, dx
test al, 0x40 ; I/O direction; 1 = FDC to CPU; 0 = CPU to FDC
jnz DataReadyFdcToCpu
LC49:
or byte [0x2], 0x20 ; last disk op: FDC failure
jmp short LC41
DataReadyFdcToCpu:
in al, 0x32 ; Read FDC data register {TRM appendix C}
mov [di], al
inc di
mov cx, 0xf ; FDC must be serviced every 26 usec {TRM 86}
.LC58:
loop .LC58
in al, dx ; Read FDC status {TRM appendix C, 85}
test al, 0x10 ; FDC read or write command in progress?
jnz .LC61
popa
ret
.LC61:
dec bl
jnz LC30
jmp short LC49
LC67:
mov al, [0x3a]
cmp al, ch
mov al, [0x3c]
jz LC7B
mov bx, 0x8
call LB36
mov al, ah
inc al
LC7B:
sub al, cl
ret
LC7E:
push es
pusha
call LD30
call LD73
jnz LCFE
mov cx, [bx+0x8]
mov ax, [bx+0x6]
call LD19
jnz LCFE
out dx, ax
mov ax, cx
inc dx
inc dx
out dx, ax
mov cx, [bx+0xc]
mov ax, [bx+0xa]
call LD19
jnz LCFE
inc dx
inc dx
out dx, ax
mov ax, cx
inc dx
inc dx
out dx, ax
mov ax, [bx+0xe]
inc dx
inc dx
out dx, ax
mov ax, 0x1900
mov es, ax
test byte [bx], 0xff
jz .setupHdPorts
mov [es:0x42], bx
mov [es:0x44], ds
jmp short LCD5
.setupHdPorts:
mov [es:0x3e], bx
mov [es:0x40], ds
call LD3C
LCD5:
mov ax, [bx+0x10]
inc dx
inc dx
out dx, ax
or al, al
jmp short LD16
LCDF:
push es
pusha
call LD3C
call LD30
add dx, byte +0x8
mov al, 0xa
LCEC:
mov cx, 0xffff
LCEF:
push ax
in ax, dx
or ax, ax
pop ax
jz LD0D
mov ah, [bx]
loop LCEF
dec al
jnz LCEC
LCFE:
stc
pushf
call LD30
add dx, byte +0xa
in ax, dx
and al, 0xfd
or al, 0x4
out dx, ax
popf
LD0D:
pushf
mov dx, [bx+0x2]
in al, dx
call LDDF
popf
LD16:
popa
pop es
ret
LD19:
push dx
mov dx, cx
mov cx, ax
mov ax, 0x10
mul dx
add ax, cx
mov cx, dx
pop dx
jnc .LD2B
inc cx
.LD2B:
test cx, 0xfff0
ret
LD30:
test byte [bx], 0xff
mov dx, 0xffc0
jz .LD3B
mov dx, 0xffd0
.LD3B:
ret
LD3C:
push dx
push ax
mov dx, 0xff30
in ax, dx
and ah, 0x7f
out dx, ax
pop ax
pop dx
ret
LD49: ; {?} hard disk interrupt handler?
pusha
push ds
mov ax, 0x1900
mov ds, ax
lds si, [0x3e]
mov dx, [si+0x2]
in al, dx
call L49F
pop ds
popa
iret
Int10: ; LD5E
pusha
push ds
mov ax, 0x1900
mov ds, ax
lds si, [0x42]
mov dx, [si+0x2]
in al, dx
call L49F
pop ds
popa
iret
LD73:
push es
pusha
mov ax, 0x1900
mov es, ax
mov cx, 0xffff
LD7D:
push cx
mov cx, 0x4
clc
xor ah, ah
mov al, [es:0x46]
LD88:
rcr al, 1
jnc LD8E
inc ah
LD8E:
loop LD88
cmp ah, 0x2
jl LD9D
pop cx
loop LD7D
dec cl
jmp short LDDC
nop
LD9D:
pop cx
mov cx, 0xffff
LDA1:
mov al, [bx+0x1]
and al, 0xf
test [es:0x46], al
jz LDB4
loop LDA1
dec cl
jmp short LDDC
nop
LDB4:
mov ah, al
rol ah, 0x4
test byte [bx], 0xff
jnz LDC8
not ah
and [es:0x46], ah
jmp short LDCA
nop
LDC8:
or al, ah
LDCA:
or [es:0x46], al
mov al, [es:0x46]
out 0x2, al ; {TRM appendix C} DMA
xor al, al
or al, [es:0x47]
LDDC:
popa
pop es
ret
LDDF:
push es
push ax
pushf
mov ax, 0x1900
mov es, ax
test byte [bx+0x10], 0xc0
jz .LDFF
mov al, [bx+0x1]
and al, 0xf
not al
and al, [es:0x46]
mov [es:0x46], al
out 0x2, al ; {TRM appendix C} DMA
.LDFF:
popf
pop ax
pop es
ret
push ds
pusha
mov ax, 0x1900
mov ds, ax
mov byte [0x47], 0xff
call L48E
popa
pop ds
iret
SetUpHDROM:
push ds
push bx
push cx
push dx
mov ax, 0x0
mov ds, ax
cli
mov word [0x1d8], IRet ; {?} int 118
mov [0x1da], cs
mov word [0x40e], 0x1a00 ; {?}
mov word [0x4c], IntFD ; int 19: floppy and hard disk
mov [0x4e], cs
mov word [0x158], IntFD ; int 86: floppy and hard disk
mov [0x15a], cs
mov word [0x104], 0x26 ; Hard disk parameter pointer {PR 194}
mov [0x106], cs ; {BUG but CS seems wrong; should be 0x1a00}
mov ax, 0x1a00 ; Copying 0x48 bytes ROM -> RAM
mov ds, ax
mov cx, 0x48
nop
mov si, HDROMImage
nop
mov di, 0x0
.copyBytes:
mov al, [cs:si]
mov [di], al
inc si
inc di
loop .copyBytes
sti
mov dx, [0x16] ; Get IO port for Cylinder LSB {TRM 189}
mov ax, 0x55aa
out dx, al
mov cx, 0xa ; 10 cycles * 125ns = 1.25us
.delay1:
loop .delay1
in al, dx ; {?} Verify the IO port retained the cylinder?
cmp al, 0xaa
jnz .badResponse
mov al, ah
out dx, al ;
mov cx, 0xa ; 10 cycles * 125ns = 1.25us
.delay2:
loop .delay2
in al, dx
cmp al, 0x55 ; {?} Verify the IO port retained the cylinder?
jz .goodResponse
.badResponse:
jmp short badResponseOut
nop
.goodResponse:
mov cx, 0x17
LE8C:
push cx
mov cx, 0x0
LE90:
push cx
mov dx, [0xa] ; Get IO port for Software Reset of WD1010 {TRM 188}
in al, dx ; Do software reset of WD1010
mov cx, 0xa
.delay:
loop .delay
mov dx, [0x1a] ; Get IO port for SDH register of WD1010 {TRM 189}
mov al, 0x20 ; Set HD0, 512 byte sectors
out dx, al
mov dx, [0x1c] ; {?} IO port 27E of WD1010 seems undefined
in al, dx
and al, 0xf0
cmp al, 0x50
pop cx
jz LEB6
loop LE90
pop cx
loop LE8C
jmp short badResponseOut
nop
LEB6:
pop cx
mov dx, 0x80 ; HD not FD
call SetUpHDROMHelper
jc setUpHDROMOut ; error?
mov dx, 0x80
call SetUpHDROMHelper1
jc setUpHDROMOut ; error?
call SetUpHDROMHelper2
jc setUpHDROMOut ; error?
call SetUpHDROMHelper1
jc setUpHDROMOut ; error?
mov byte [0x3], 0x1 ; {?} set some success flag?
jmp short setUpHDROMOut
nop
SetUpHDROMHelper1:
mov ax, 0x1101 ; {?}
mov cx, 0x1
int 86 ; Int86FDHD
ret
SetUpHDROMHelper2:
mov cx, 0x501
mov ax, 0xc01 ; {?}
int 86 ; Int86FDHD
ret
badResponseOut:
mov ah, 0x7 ; {?}
stc ; Set carry to denote error
jmp short setUpHDROMOut
; {?} perhaps success route? from where?
nop
sub ah, ah
setUpHDROMOut:
pop dx
pop cx
pop bx
pop ds
ret
SetUpHDROMHelper:
mov ax, 0x0 ; reset {?}
mov cx, 0x1 ; {?}
int 86 ; Int86FDHD
ret
; {?} 8 tmp
; indirects for HD IO ports
HDROMImage: ; LF01
db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x6C, 0x02, 0x70, 0x02, 0x72
LF10:
db 0x02, 0x72, 0x02, 0x74, 0x02, 0x76, 0x02, 0x78, 0x02, 0x7A, 0x02, 0x7C, 0x02, 0x7E, 0x02, 0x7E
LF20:
db 0x02, 0x00, 0x00, 0x00, 0x00, 0x20, 0x00, 0x32, 0x01, 0x04, 0x00, 0x00, 0x20, 0x00, 0x00, 0x00
LF30:
db 0x02, 0x02, 0x1C, 0x04, 0x00, 0x00, 0x00, 0x00, 0x32, 0x01, 0x04, 0x00, 0x00, 0x20, 0x00, 0x00
LF40:
db 0x00, 0x02, 0x02, 0x1C, 0x04, 0x00, 0x00, 0x00, 0x00
LF49:
db 0x15, 0x00, 0xB2, 0x0F, ; {?} LFB2
db 0xFF, 0x0F, 0x75, 0x10,
LF51:
db 0x1B, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75
LF60:
db 0x10, 0x75, 0x10, 0x75, 0x10, 0x4B, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10, 0x60
LF70:
db 0x10, 0x75, 0x10, 0x75, 0x10, 0x75, 0x10
IntFD:
cmp dl, 0x80
jz .wantFloppy ; Not requesting hard disk?
mov ah, 0x1 ; Wanted HD, but not supported!
stc
ret 0x2
.wantFloppy:
push di
mov di, 0xf49
sti
push ds ; .LF87
push es
pusha
cmp ah, [cs:di]
jnc LFA8
mov bp, sp
cld
push ax
call near [cs:di+0x2]
pop ax
push ax
mov al, ah
xor ah, ah
add ax, ax
add di, ax
pop ax
call near [cs:di+0x4]
jmp short LFAD
LFA8:
mov al, 0x1
mov [bp+0xf], al
LFAD:
popa
pop es
pop ds
pop di
iret
LFB2: ; {?} possibly called via offset from chunk at LF01. disk related.
push ax
mov ax, 0x1a00 ; Switch DS to 0x1a00
mov ds, ax
pop ax
mov [0x8], bx ; {?} who calls, and what is bx?
mov [0x20], al ; {?} who calls, and what is al?
mov al, cl
and al, 0xc0
shr al, 0x6 ; {?} get bit 0xc0
mov [0x23], al
and cl, 0x3f
mov [0x21], cl
mov [0x22], ch
mov al, [0x24]
and al, 0x60
and dl, 0x1
mov [0x2], dl
mov cl, 0x3
shl dl, cl
or dl, dh
or al, dl
mov [0x24], al
mov byte [0x25], 0x0
mov al, [0x2]
call L10f5
mov [0x0], si ; [0x1a000] is sum of ?
call L10DC
ret
mov dx, [0xa]
in al, dx
mov cx, 0xa
.L1007:
loop .L1007
mov dx, [0x1c]
in al, dx
and al, 0xf0
cmp al, 0x50
jz L1018
mov ah, 0x5
stc
ret
L1018:
sub ah, ah
ret
mov byte [0x25], 0x20
mov ch, 0x0
mov cl, [0x20]
L1026:
call L1119
mov si, [0x0]
mov bl, [si+0x9]
call L1133
jc L1040
call L10A1
jc L1048
inc byte [0x21]
loop L1026
L1040:
mov al, [0x20]
sub al, cl
mov [bp+0xe], al
L1048:
jmp short .L107F
nop
mov byte [0x25], 0x70
call L1119
mov si, [0x0]
mov bl, [si+0x9]
call L1133
jmp short .L107F
nop
mov byte [0x25], 0x10
call L1119
mov si, [0x0]
mov bl, [si+0xb]
call L1133
jmp short .L107F
nop
mov ah, 0x1
jmp short .L107F
nop
mov ah, 0x0
jmp short .L107F
nop
.L107F:
mov [0x5], ah
mov [bp+0xf], ah
or ah, ah
jz L1097
call L110A
stc
lahf
mov [bp+0x1a], ah
mov ah, [0x5]
ret
L1097:
clc
lahf
mov [bp+0x1a], ah
mov ah, [0x5]
ret
L10A1:
push cx
push dx
mov cx, 0x0
mov dx, [0x1c]
L10AA:
in al, dx
test al, 0x8
jnz L10B7
loop L10AA
mov ah, 0x80
stc
jmp short L10D9
nop
L10B7:
mov cx, 0x200
mov dx, [0xc]
mov bx, [0x8]
cld
L10C3:
in al, dx
mov [es:bx], al
inc bx
jnz L10D1
mov ax, es
add ax, 0x1000
mov es, ax
L10D1:
loop L10C3
mov [0x8], bx
sub ah, ah
L10D9:
pop dx
pop cx
ret
; ds is 0x1a00
L10DC: ; {? perhaps HD reset}
push ax
push dx
mov al, [0x24]
mov dx, [0x1a] ; 27C; set SDH register of WD1010; {TRM 189}
out dx, al
mov si, [0x0]
mov ax, [si+0x5]
mov dx, [0x10] ; 272; write precomp {TRM 188}
out dx, al
pop dx
pop ax
ret
; DS is 0x1a000
L10f5:
mov cl, [0x2]
mov al, cl
mov ch, 0x0
mov si, 0x26
or cl, cl
jz .done
.L1104:
add si, byte +0x11
loop .L1104
.done:
ret
L110A:
push ax
push dx
mov dx, [0xa]
in al, dx
mov cx, 0xa
.L1114:
loop .L1114
pop dx
pop ax
ret
L1119:
push ax
push cx
push dx
push si
mov cx, 0x6
mov si, 0x20
mov dx, [0x12]
cld
.L1128:
lodsb
out dx, al
inc dx
inc dx
loop .L1128
pop si
pop dx
pop cx
pop ax
ret
L1133:
push cx
push dx
mov dx, [0x1c]
sub cx, cx
.L113B:
in al, dx
mov ah, al
in al, dx
cmp ah, al
jnz .L113B
and al, 0xf0
cmp al, 0x50
jz .L1154
loop .L113B
dec bl
jnz .L113B
mov ah, 0x80
jmp short .L1164
nop
.L1154:
mov al, ah
test al, 0x1
jz .L1167
mov dx, [0xe]
in al, dx
and al, 0xd6
call L116C
.L1164:
stc
jmp short .L1169
.L1167:
sub ah, ah
.L1169:
pop dx
pop cx
ret
L116C:
test al, 0x1
jz .L1173
mov ah, 0x2
ret
.L1173:
test al, 0x2
jz .L117A
mov ah, 0x40
ret
.L117A:
test al, 0x4
jz .L1181
mov ah, 0x1
ret
.L1181:
test al, 0x10
jz .L1188
mov ah, 0x4
ret
.L1188:
test al, 0x40
jz .L118F
mov ah, 0x10
ret
.L118F:
test al, 0x80
jz .L1196
mov ah, 0xb
ret
.L1196:
mov ah, 0xbb
ret
IRet:
iret
;; padding
L119a: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L11a0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L11b0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L11c0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L11d0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L11e0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L11f0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1200: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1210: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1220: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1230: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1240: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1250: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1260: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1270: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1280: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1290: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L12a0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L12b0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L12c0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L12d0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L12e0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L12f0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
; Character set
CharSet8x8:
L1300: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3c, 0x42, 0xa5, 0x81, 0xa5, 0x99, 0x42, 0x3c
L1310: db 0xc3, 0xbd, 0x5a, 0x7e, 0x5a, 0x66, 0xbd, 0xc3, 0x22, 0x77, 0x7f, 0x7f, 0x3e, 0x1c, 0x08, 0x00
L1320: db 0x08, 0x1c, 0x3e, 0x7f, 0x3e, 0x1c, 0x08, 0x00, 0x1c, 0x08, 0x49, 0x7f, 0x49, 0x08, 0x3e, 0x00
L1330: db 0x08, 0x1c, 0x3e, 0x7f, 0x2a, 0x08, 0x3e, 0x00, 0x00, 0x00, 0x18, 0x3c, 0x3c, 0x18, 0x00, 0x00
L1340: db 0xff, 0xff, 0xe7, 0xc3, 0xc3, 0xe7, 0xff, 0xff, 0x00, 0x3c, 0x42, 0x42, 0x42, 0x3c, 0x00, 0x00
L1350: db 0xff, 0xc3, 0xbd, 0xbd, 0xbd, 0xc3, 0xff, 0xff, 0x0f, 0x03, 0x05, 0x38, 0x44, 0x44, 0x38, 0x00
L1360: db 0x1c, 0x22, 0x22, 0x1c, 0x08, 0x3e, 0x08, 0x00, 0x1f, 0x11, 0x11, 0x1f, 0x10, 0x30, 0x70, 0x00
L1370: db 0x3f, 0x21, 0x21, 0x3f, 0x21, 0x22, 0x40, 0x00, 0x49, 0x2a, 0x36, 0x63, 0x36, 0x2a, 0x49, 0x00
L1380: db 0x40, 0x70, 0x7c, 0x7f, 0x7c, 0x70, 0x40, 0x00, 0x01, 0x07, 0x1f, 0x7f, 0x1f, 0x07, 0x01, 0x00
L1390: db 0x08, 0x1c, 0x2a, 0x08, 0x08, 0x2a, 0x1c, 0x08, 0x24, 0x24, 0x24, 0x24, 0x24, 0x00, 0x24, 0x00
L13a0: db 0x3f, 0x49, 0x49, 0x49, 0x39, 0x09, 0x09, 0x00, 0x18, 0x20, 0x1c, 0x22, 0x1c, 0x02, 0x0c, 0x00
L13b0: db 0x00, 0x00, 0x00, 0x7e, 0x7e, 0x7e, 0x7e, 0x00, 0x08, 0x1c, 0x2a, 0x08, 0x2a, 0x1c, 0x08, 0xff
L13c0: db 0x08, 0x1c, 0x2a, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x2a, 0x1c, 0x08
L13d0: db 0x00, 0x04, 0x02, 0xff, 0x02, 0x04, 0x00, 0x00, 0x00, 0x20, 0x40, 0xff, 0x40, 0x20, 0x00, 0x00
L13e0: db 0x00, 0x40, 0x40, 0x40, 0x40, 0x7e, 0x00, 0x00, 0x00, 0x24, 0x42, 0xff, 0x42, 0x24, 0x00, 0x00
L13f0: db 0x00, 0x08, 0x1c, 0x3e, 0x7f, 0x7f, 0x00, 0x00, 0x00, 0x7f, 0x7f, 0x3e, 0x1c, 0x08, 0x00, 0x00
L1400: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x08, 0x00
L1410: db 0x14, 0x14, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x14, 0x14, 0x3e, 0x14, 0x3e, 0x14, 0x14, 0x00
L1420: db 0x08, 0x1e, 0x28, 0x1c, 0x0a, 0x3c, 0x08, 0x00, 0x00, 0x62, 0x64, 0x08, 0x10, 0x26, 0x46, 0x00
L1430: db 0x30, 0x48, 0x48, 0x30, 0x4a, 0x44, 0x3a, 0x00, 0x08, 0x08, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00
L1440: db 0x04, 0x08, 0x10, 0x10, 0x10, 0x08, 0x04, 0x00, 0x10, 0x08, 0x04, 0x04, 0x04, 0x08, 0x10, 0x00
L1450: db 0x00, 0x22, 0x14, 0x3e, 0x14, 0x22, 0x00, 0x00, 0x00, 0x08, 0x08, 0x3e, 0x08, 0x08, 0x00, 0x00
L1460: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x08, 0x10, 0x00, 0x00, 0x00, 0x7e, 0x00, 0x00, 0x00, 0x00
L1470: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x00
L1480: db 0x3e, 0x43, 0x45, 0x49, 0x51, 0x61, 0x3e, 0x00, 0x08, 0x18, 0x28, 0x08, 0x08, 0x08, 0x3e, 0x00
L1490: db 0x3e, 0x41, 0x06, 0x18, 0x20, 0x40, 0x7f, 0x00, 0x3e, 0x41, 0x01, 0x1e, 0x01, 0x41, 0x3e, 0x00
L14a0: db 0x06, 0x0a, 0x12, 0x22, 0x7f, 0x02, 0x02, 0x00, 0x7e, 0x40, 0x7c, 0x02, 0x01, 0x42, 0x3c, 0x00
L14b0: db 0x18, 0x20, 0x40, 0x7e, 0x41, 0x41, 0x3e, 0x00, 0x7f, 0x41, 0x02, 0x04, 0x08, 0x08, 0x08, 0x00
L14c0: db 0x3e, 0x41, 0x41, 0x3e, 0x41, 0x41, 0x3e, 0x00, 0x3e, 0x41, 0x41, 0x3f, 0x01, 0x02, 0x0c, 0x00
L14d0: db 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x08, 0x08, 0x10
L14e0: db 0x00, 0x04, 0x08, 0x10, 0x08, 0x04, 0x00, 0x00, 0x00, 0x00, 0x7e, 0x00, 0x7e, 0x00, 0x00, 0x00
L14f0: db 0x00, 0x10, 0x08, 0x04, 0x08, 0x10, 0x00, 0x00, 0x3c, 0x42, 0x02, 0x0c, 0x10, 0x00, 0x10, 0x00
L1500: db 0x1e, 0x21, 0x4d, 0x55, 0x4e, 0x20, 0x1e, 0x00, 0x08, 0x14, 0x22, 0x41, 0x7f, 0x41, 0x41, 0x00
L1510: db 0x7e, 0x21, 0x21, 0x3e, 0x21, 0x21, 0x7e, 0x00, 0x1e, 0x21, 0x40, 0x40, 0x40, 0x21, 0x1e, 0x00
L1520: db 0x7c, 0x22, 0x21, 0x21, 0x21, 0x22, 0x7c, 0x00, 0x7f, 0x40, 0x40, 0x7c, 0x40, 0x40, 0x7f, 0x00
L1530: db 0x7f, 0x40, 0x40, 0x7c, 0x40, 0x40, 0x40, 0x00, 0x1e, 0x21, 0x40, 0x4f, 0x41, 0x21, 0x1e, 0x00
L1540: db 0x41, 0x41, 0x41, 0x7f, 0x41, 0x41, 0x41, 0x00, 0x1c, 0x08, 0x08, 0x08, 0x08, 0x08, 0x1c, 0x00
L1550: db 0x0e, 0x04, 0x04, 0x04, 0x04, 0x24, 0x18, 0x00, 0x41, 0x42, 0x44, 0x78, 0x44, 0x42, 0x41, 0x00
L1560: db 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x7f, 0x00, 0x41, 0x63, 0x55, 0x49, 0x41, 0x41, 0x41, 0x00
L1570: db 0x41, 0x61, 0x51, 0x49, 0x45, 0x43, 0x41, 0x00, 0x3e, 0x41, 0x41, 0x41, 0x41, 0x41, 0x3e, 0x00
L1580: db 0x7e, 0x41, 0x41, 0x7e, 0x40, 0x40, 0x40, 0x00, 0x3e, 0x41, 0x41, 0x41, 0x45, 0x42, 0x3d, 0x00
L1590: db 0x7e, 0x41, 0x41, 0x7e, 0x44, 0x42, 0x41, 0x00, 0x3e, 0x41, 0x40, 0x3e, 0x01, 0x41, 0x3e, 0x00
L15a0: db 0x7f, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x3e, 0x00
L15b0: db 0x41, 0x41, 0x22, 0x22, 0x14, 0x14, 0x08, 0x00, 0x41, 0x41, 0x49, 0x49, 0x55, 0x63, 0x22, 0x00
L15c0: db 0x41, 0x22, 0x14, 0x08, 0x14, 0x22, 0x41, 0x00, 0x41, 0x41, 0x22, 0x14, 0x08, 0x08, 0x08, 0x00
L15d0: db 0x7f, 0x02, 0x04, 0x08, 0x10, 0x20, 0x7f, 0x00, 0x1c, 0x10, 0x10, 0x10, 0x10, 0x10, 0x1c, 0x00
L15e0: db 0x00, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x00, 0x1c, 0x04, 0x04, 0x04, 0x04, 0x04, 0x1c, 0x00
L15f0: db 0x08, 0x14, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff
L1600: db 0x08, 0x08, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x3c, 0x02, 0x3e, 0x42, 0x3d, 0x00
L1610: db 0x40, 0x40, 0x5c, 0x62, 0x42, 0x62, 0x5c, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x40, 0x42, 0x3c, 0x00
L1620: db 0x02, 0x02, 0x3a, 0x46, 0x42, 0x46, 0x3a, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x7e, 0x40, 0x3c, 0x00
L1630: db 0x04, 0x0a, 0x08, 0x3e, 0x08, 0x08, 0x08, 0x00, 0x00, 0x00, 0x3a, 0x46, 0x46, 0x3a, 0x02, 0x3c
L1640: db 0x40, 0x40, 0x5c, 0x62, 0x42, 0x42, 0x42, 0x00, 0x08, 0x00, 0x18, 0x08, 0x08, 0x08, 0x1c, 0x00
L1650: db 0x04, 0x00, 0x0c, 0x04, 0x04, 0x04, 0x24, 0x18, 0x20, 0x20, 0x22, 0x24, 0x28, 0x34, 0x22, 0x00
L1660: db 0x18, 0x08, 0x08, 0x08, 0x08, 0x08, 0x1c, 0x00, 0x00, 0x00, 0x76, 0x49, 0x49, 0x49, 0x49, 0x00
L1670: db 0x00, 0x00, 0x5c, 0x62, 0x42, 0x42, 0x42, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x42, 0x42, 0x3c, 0x00
L1680: db 0x00, 0x00, 0x5c, 0x62, 0x62, 0x5c, 0x40, 0x40, 0x00, 0x00, 0x3a, 0x46, 0x46, 0x3a, 0x02, 0x02
L1690: db 0x00, 0x00, 0x5c, 0x62, 0x40, 0x40, 0x40, 0x00, 0x00, 0x00, 0x3e, 0x40, 0x3c, 0x02, 0x7c, 0x00
L16a0: db 0x10, 0x10, 0x7c, 0x10, 0x10, 0x12, 0x0c, 0x00, 0x00, 0x00, 0x42, 0x42, 0x42, 0x46, 0x3a, 0x00
L16b0: db 0x00, 0x00, 0x42, 0x42, 0x42, 0x24, 0x18, 0x00, 0x00, 0x00, 0x41, 0x49, 0x55, 0x63, 0x22, 0x00
L16c0: db 0x00, 0x00, 0x42, 0x24, 0x18, 0x24, 0x42, 0x00, 0x00, 0x00, 0x42, 0x42, 0x46, 0x3a, 0x02, 0x3c
L16d0: db 0x00, 0x00, 0x3e, 0x04, 0x08, 0x10, 0x3e, 0x00, 0x0c, 0x10, 0x10, 0x20, 0x10, 0x10, 0x0c, 0x00
L16e0: db 0x08, 0x08, 0x08, 0x00, 0x08, 0x08, 0x08, 0x00, 0x30, 0x08, 0x08, 0x04, 0x08, 0x08, 0x30, 0x00
L16f0: db 0x32, 0x4c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x14, 0x22, 0x41, 0x7f, 0x00
; Character set
CharSet8x16:
L1700: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ; 0: null
L1710: db 0x00, 0x3c, 0x42, 0x81, 0xa5, 0x81, 0xa5, 0x99, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ; 1: smiley
L1720: db 0x00, 0xc3, 0xbd, 0x7e, 0x5a, 0x7e, 0x5a, 0x66, 0xbd, 0xc3, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 ; 2: inverse smiley
L1730: db 0x00, 0x00, 0x22, 0x77, 0x7f, 0x7f, 0x3e, 0x1c, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1740: db 0x00, 0x00, 0x08, 0x1c, 0x3e, 0x7f, 0x3e, 0x1c, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1750: db 0x00, 0x00, 0x1c, 0x08, 0x49, 0x7f, 0x49, 0x08, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1760: db 0x00, 0x00, 0x08, 0x1c, 0x3e, 0x7f, 0x2a, 0x08, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1770: db 0x00, 0x00, 0x00, 0x00, 0x18, 0x3c, 0x3c, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1780: db 0x00, 0xff, 0xff, 0xff, 0xe7, 0xc3, 0xc3, 0xe7, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1790: db 0x00, 0x00, 0x00, 0x3c, 0x42, 0x42, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L17a0: db 0x00, 0xff, 0xff, 0xc3, 0xbd, 0xbd, 0xbd, 0xc3, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L17b0: db 0x00, 0x0f, 0x03, 0x05, 0x39, 0x44, 0x82, 0x82, 0x44, 0x38, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L17c0: db 0x00, 0x00, 0x00, 0x00, 0x1c, 0x22, 0x41, 0x41, 0x22, 0x1c, 0x08, 0x3e, 0x08, 0x00, 0x00, 0x00
L17d0: db 0x00, 0x00, 0x1f, 0x11, 0x11, 0x1f, 0x10, 0x10, 0x10, 0x30, 0x70, 0x00, 0x00, 0x00, 0x00, 0x00
L17e0: db 0x00, 0x00, 0x3f, 0x21, 0x21, 0x3f, 0x21, 0x21, 0x21, 0x22, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00
L17f0: db 0x00, 0x00, 0x49, 0x2a, 0x36, 0x63, 0x36, 0x2a, 0x49, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1800: db 0x00, 0x00, 0x40, 0x70, 0x7c, 0x7f, 0x7c, 0x70, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1810: db 0x00, 0x00, 0x01, 0x07, 0x1f, 0x7f, 0x1f, 0x07, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1820: db 0x08, 0x1c, 0x2a, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x2a, 0x1c, 0x08
L1830: db 0x00, 0x24, 0x24, 0x24, 0x24, 0x24, 0x24, 0x24, 0x00, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1840: db 0x00, 0x00, 0x3f, 0x49, 0x49, 0x49, 0x49, 0x39, 0x09, 0x09, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1850: db 0x00, 0x00, 0x1e, 0x21, 0x1c, 0x22, 0x22, 0x1c, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1860: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x7e, 0x7e, 0x7e, 0x7e, 0x7e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1870: db 0x08, 0x1c, 0x2a, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x2a, 0x1c, 0x08, 0xff
L1880: db 0x08, 0x1c, 0x2a, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08
L1890: db 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x2a, 0x1c, 0x08
L18a0: db 0x00, 0x00, 0x00, 0x04, 0x02, 0xff, 0x02, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L18b0: db 0x00, 0x00, 0x00, 0x20, 0x40, 0xff, 0x40, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L18c0: db 0x00, 0x00, 0x00, 0x40, 0x40, 0x40, 0x40, 0x7e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L18d0: db 0x00, 0x00, 0x00, 0x24, 0x42, 0xff, 0x42, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L18e0: db 0x00, 0x00, 0x00, 0x08, 0x1c, 0x3e, 0x7f, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L18f0: db 0x00, 0x00, 0x00, 0x7f, 0x7f, 0x3e, 0x1c, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1900: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1910: db 0x00, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1920: db 0x00, 0x14, 0x14, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1930: db 0x00, 0x24, 0x24, 0x24, 0x7e, 0x24, 0x7e, 0x24, 0x24, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1940: db 0x00, 0x08, 0x3f, 0x48, 0x48, 0x3e, 0x09, 0x09, 0x7e, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1950: db 0x00, 0x20, 0x51, 0x22, 0x04, 0x08, 0x10, 0x22, 0x45, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1960: db 0x00, 0x10, 0x28, 0x28, 0x10, 0x28, 0x44, 0x45, 0x42, 0x3d, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1970: db 0x00, 0x08, 0x08, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1980: db 0x00, 0x04, 0x08, 0x10, 0x10, 0x10, 0x10, 0x10, 0x08, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1990: db 0x00, 0x10, 0x08, 0x04, 0x04, 0x04, 0x04, 0x04, 0x08, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L19a0: db 0x00, 0x00, 0x00, 0x24, 0x18, 0x7e, 0x18, 0x24, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L19b0: db 0x00, 0x00, 0x00, 0x08, 0x08, 0x3e, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L19c0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x08, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00
L19d0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x7e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L19e0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L19f0: db 0x00, 0x00, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a00: db 0x00, 0x3e, 0x41, 0x43, 0x45, 0x49, 0x51, 0x61, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a10: db 0x00, 0x08, 0x18, 0x28, 0x08, 0x08, 0x08, 0x08, 0x08, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a20: db 0x00, 0x3e, 0x41, 0x01, 0x02, 0x0c, 0x30, 0x40, 0x40, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a30: db 0x00, 0x3e, 0x41, 0x01, 0x01, 0x1e, 0x01, 0x01, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a40: db 0x00, 0x02, 0x06, 0x0a, 0x12, 0x22, 0x7f, 0x02, 0x02, 0x02, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a50: db 0x00, 0x7e, 0x40, 0x40, 0x7c, 0x02, 0x01, 0x01, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a60: db 0x00, 0x0c, 0x10, 0x20, 0x40, 0x7c, 0x42, 0x41, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a70: db 0x00, 0x7f, 0x41, 0x01, 0x02, 0x04, 0x08, 0x08, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a80: db 0x00, 0x3e, 0x41, 0x41, 0x41, 0x3e, 0x41, 0x41, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1a90: db 0x00, 0x3e, 0x41, 0x41, 0x41, 0x3f, 0x01, 0x02, 0x04, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1aa0: db 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ab0: db 0x00, 0x00, 0x00, 0x00, 0x08, 0x00, 0x00, 0x00, 0x08, 0x08, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00
L1ac0: db 0x00, 0x00, 0x04, 0x08, 0x10, 0x20, 0x10, 0x08, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ad0: db 0x00, 0x00, 0x00, 0x00, 0x7e, 0x00, 0x7e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ae0: db 0x00, 0x00, 0x20, 0x10, 0x08, 0x04, 0x08, 0x10, 0x20, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1af0: db 0x00, 0x3c, 0x42, 0x02, 0x04, 0x08, 0x10, 0x10, 0x00, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b00: db 0x00, 0x1e, 0x21, 0x4d, 0x55, 0x51, 0x4e, 0x40, 0x40, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b10: db 0x00, 0x08, 0x14, 0x22, 0x41, 0x41, 0x7f, 0x41, 0x41, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b20: db 0x00, 0x7e, 0x41, 0x41, 0x41, 0x7e, 0x41, 0x41, 0x41, 0x7e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b30: db 0x00, 0x3e, 0x41, 0x40, 0x40, 0x40, 0x40, 0x40, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b40: db 0x00, 0x7c, 0x42, 0x41, 0x41, 0x41, 0x41, 0x41, 0x42, 0x7c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b50: db 0x00, 0x7f, 0x40, 0x40, 0x40, 0x7c, 0x40, 0x40, 0x40, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b60: db 0x00, 0x7f, 0x40, 0x40, 0x40, 0x7c, 0x40, 0x40, 0x40, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b70: db 0x00, 0x1e, 0x21, 0x40, 0x40, 0x4f, 0x41, 0x41, 0x21, 0x1e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b80: db 0x00, 0x41, 0x41, 0x41, 0x41, 0x7f, 0x41, 0x41, 0x41, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1b90: db 0x00, 0x1c, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ba0: db 0x00, 0x0e, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x44, 0x38, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1bb0: db 0x00, 0x41, 0x42, 0x44, 0x48, 0x50, 0x68, 0x44, 0x42, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1bc0: db 0x00, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x40, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1bd0: db 0x00, 0x41, 0x63, 0x55, 0x49, 0x49, 0x41, 0x41, 0x41, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1be0: db 0x00, 0x41, 0x41, 0x61, 0x51, 0x49, 0x45, 0x43, 0x41, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1bf0: db 0x00, 0x3e, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c00: db 0x00, 0x7e, 0x41, 0x41, 0x41, 0x7e, 0x40, 0x40, 0x40, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c10: db 0x00, 0x3e, 0x41, 0x41, 0x41, 0x41, 0x49, 0x45, 0x42, 0x3d, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c20: db 0x00, 0x7e, 0x41, 0x41, 0x41, 0x7e, 0x48, 0x44, 0x42, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c30: db 0x00, 0x3e, 0x41, 0x40, 0x40, 0x3e, 0x01, 0x01, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c40: db 0x00, 0x7f, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c50: db 0x00, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x41, 0x3e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c60: db 0x00, 0x41, 0x41, 0x41, 0x22, 0x22, 0x14, 0x14, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c70: db 0x00, 0x41, 0x41, 0x41, 0x41, 0x49, 0x49, 0x55, 0x63, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c80: db 0x00, 0x41, 0x41, 0x22, 0x14, 0x08, 0x14, 0x22, 0x41, 0x41, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1c90: db 0x00, 0x41, 0x41, 0x41, 0x22, 0x14, 0x08, 0x08, 0x08, 0x08, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ca0: db 0x00, 0x7f, 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1cb0: db 0x00, 0x1c, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1cc0: db 0x00, 0x00, 0x40, 0x20, 0x10, 0x08, 0x04, 0x02, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1cd0: db 0x00, 0x1c, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ce0: db 0x00, 0x08, 0x14, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1cf0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0x00, 0x00, 0x00, 0x00
L1d00: db 0x00, 0x08, 0x08, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d10: db 0x00, 0x00, 0x00, 0x00, 0x3c, 0x02, 0x3e, 0x42, 0x42, 0x3d, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d20: db 0x00, 0x40, 0x40, 0x40, 0x5c, 0x62, 0x42, 0x42, 0x62, 0x5c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d30: db 0x00, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x40, 0x40, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d40: db 0x00, 0x02, 0x02, 0x02, 0x3a, 0x46, 0x42, 0x42, 0x46, 0x3a, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d50: db 0x00, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x7e, 0x40, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d60: db 0x00, 0x0c, 0x12, 0x10, 0x10, 0x7c, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d70: db 0x00, 0x00, 0x00, 0x00, 0x3a, 0x46, 0x42, 0x42, 0x46, 0x3a, 0x02, 0x02, 0x02, 0x1c, 0x00, 0x00
L1d80: db 0x00, 0x40, 0x40, 0x40, 0x5c, 0x62, 0x42, 0x42, 0x42, 0x42, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1d90: db 0x00, 0x00, 0x08, 0x00, 0x18, 0x08, 0x08, 0x08, 0x08, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1da0: db 0x00, 0x00, 0x08, 0x00, 0x18, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x48, 0x30, 0x00, 0x00
L1db0: db 0x00, 0x40, 0x40, 0x40, 0x44, 0x48, 0x50, 0x68, 0x44, 0x42, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1dc0: db 0x00, 0x18, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x08, 0x1c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1dd0: db 0x00, 0x00, 0x00, 0x00, 0x76, 0x49, 0x49, 0x49, 0x49, 0x49, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1de0: db 0x00, 0x00, 0x00, 0x00, 0x5c, 0x62, 0x42, 0x42, 0x42, 0x42, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1df0: db 0x00, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x42, 0x42, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e00: db 0x00, 0x00, 0x00, 0x00, 0x5c, 0x62, 0x42, 0x42, 0x62, 0x5c, 0x40, 0x40, 0x40, 0x40, 0x00, 0x00
L1e10: db 0x00, 0x00, 0x00, 0x00, 0x3a, 0x46, 0x42, 0x42, 0x46, 0x3a, 0x02, 0x02, 0x02, 0x02, 0x00, 0x00
L1e20: db 0x00, 0x00, 0x00, 0x00, 0x5c, 0x62, 0x40, 0x40, 0x40, 0x40, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e30: db 0x00, 0x00, 0x00, 0x00, 0x3c, 0x42, 0x30, 0x0c, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e40: db 0x00, 0x10, 0x10, 0x10, 0x7c, 0x10, 0x10, 0x10, 0x12, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e50: db 0x00, 0x00, 0x00, 0x00, 0x42, 0x42, 0x42, 0x42, 0x42, 0x3c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e60: db 0x00, 0x00, 0x00, 0x00, 0x42, 0x42, 0x42, 0x24, 0x18, 0x18, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e70: db 0x00, 0x00, 0x00, 0x00, 0x41, 0x49, 0x49, 0x55, 0x63, 0x22, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e80: db 0x00, 0x00, 0x00, 0x00, 0x42, 0x24, 0x18, 0x18, 0x24, 0x42, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1e90: db 0x00, 0x00, 0x00, 0x00, 0x42, 0x42, 0x42, 0x42, 0x46, 0x3a, 0x02, 0x02, 0x02, 0x1c, 0x00, 0x00
L1ea0: db 0x00, 0x00, 0x00, 0x00, 0x7e, 0x04, 0x08, 0x10, 0x20, 0x7e, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1eb0: db 0x00, 0x0c, 0x10, 0x10, 0x10, 0x20, 0x10, 0x10, 0x10, 0x0c, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ec0: db 0x00, 0x10, 0x10, 0x10, 0x10, 0x00, 0x10, 0x10, 0x10, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ed0: db 0x00, 0x30, 0x08, 0x08, 0x08, 0x04, 0x08, 0x08, 0x08, 0x30, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ee0: db 0x00, 0x30, 0x49, 0x06, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1ef0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x08, 0x14, 0x22, 0x41, 0x7f, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
;; Power on: CS=0xff0, IP=0
PowerOn: ; L1f00
mov ax, 0xff
mov dx, 0xfffe ; {? port 0xfffe}
out dx, ax
mov bx, ax ; bx = 0xff
not ax ; ax = 0
mov dx, 0xfffe
in ax, dx
xor ax, bx
and ax, 0xdfff ; {? what is reading from port 0xfffe telling us?)
jz .continue
.hang:
jmp short .hang
.continue: ; L1f18
mov ax, 0xc0be
mov dx, 0xffa8
out dx, ax ; {? port 0xffa8}
mov ax, 0x1f8
mov dx, 0xffa6
out dx, ax
mov ax, 0x3e
mov dx, 0xffa4
out dx, ax
mov al, 0x0
mov dx, 0x0
out dx, al ; {TRM appendix C, turn off devices}
mov al, 0xc0
mov dx, 0x101
out dx, al ; {TRM appendix C, video: 800x400, bus not 9007}
mov dx, 0x56
mov al, 0xaa
out dx, al ; {? port 0x56}
nop
nop
mov dx, 0x54
mov al, 0x5
out dx, al ; {TRM appendix C, 8255 direction, read keyboard}
mov al, 0x3
mov dx, 0x52
%ifdef DEBUG
in al, dx ; {?} Guessing something like this may have been in original
; source. Allows selection of different hardware setup.
%else
nop ; Release builds always leave al=3
%endif
mov bp, 0x1f6a
nop
.checkProfile:
cmp al, [cs:bp+0x0]
je .foundProfile
add bp, byte +0x10
jmp short .checkProfile
.foundProfile: ;L1f5c:
mov ax, [cs:bp+0x2]
mov dx, 0xffa0
out dx, ax
jmp word 0xfe00:0x0 ; Jump to StartOfBoot
nop
; Hardware Profiles (or so I call them)
; cs:bp is set (in PowerOn) to point to one of these 4 16-byte blocks. Describes hardware.
; Maybe for debug vs production, or hardware revisions?
; 0 index (influences font setup)
; 1 max allowed 64k banks of RAM
; 2 is written to IO port 0xffa0 {? why?}
; 3
; 4 Address Control Register {TRM appendix C} when 128k installed
; 5 Device power-on, reset, DMA 8237, etc
L1f6a: db 0x00, 0x08, 0x3f, 0xe0, 0x44, 0x00, 0x48, 0x00, 0x50, 0x00, 0x60, 0x00, 0x60, 0x00, 0x60, 0x00
L1f7a: db 0x01, 0x08, 0x3b, 0xe0, 0xc4, 0x00, 0xc8, 0x00, 0xd0, 0x00, 0xe0, 0x00, 0xe0, 0x00, 0xe0, 0x00
L1f8a: db 0x02, 0x0c, 0x3f, 0xf8, 0xc3, 0x00, 0xc7, 0x00, 0xcb, 0x00, 0xcf, 0x00, 0xd3, 0x00, 0xd7, 0x00
L1f9a: db 0x03, 0x0c, 0x3f, 0xf8, 0xc3, 0x10, 0xc7, 0x10, 0xcb, 0x10, 0xcf, 0x10, 0xd3, 0x10, 0xd7, 0x10
L1faa: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1fb0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1fc0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1fd0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00
L1fe0: db 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xfd, 0x3a
L1ff0: db 0xea, 0x00, 0x1f, 0x00, 0xfe, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00