CMOS Memory Dump (IBM-PC and Compatibles) msu@mix Ver.1.0 Sep.25 92
Reference: The Programmer's PC sourcebook, Thom Hogan, 1988, (P.183...186)

Loc.  Value	Descriptions			 Comments
----- --------  -------------------------------- ------------------------------
40:00 %04.4x	COM1 base address		|
40:02 %04.4x	COM2 base address		|
40:04 %04.4x	COM3 base address		|supported only PS/2 BIOS
40:06 %04.4x	COM4 base address		|supported only PS/2 BIOS
40:08 %04.4x	LPT1 base address		|
40:0A %04.4x	LPT2 base address		|
40:0C %04.4x	LPT3 base address		|
40:0E %04.4x	LPT4 base address		|
40:10 %02.2x	Installed hardware 1		!
      xx......	|number of floppy device (0-based)
     =..00....	|video mode (unknown)
     =..01....	|video mode (40x25 color)
     =..10....	|video mode (80x25 color)
     =..11....	|video mode (80x25 mono)
      ....xx..	|reserved (old PC and PCJr)
      .....x..	|pointing device installed (PS/2)
      ......x.	|math coprecessor installed
      .......x	|floppy drives installed
40:11 %02.2x	Installed hardware 2		!
      xx......	|number of printer adapters
      ..x.....	|internal modem(Convertive only)
      ...x....	|joystick installed
      ....xxx.	|number of RS-232 adapters
      .......x	|reserved (PCJr=DMA device installed)
40:12 %02.2x	Power-on self test status	|
40:13 %04.4x	Memory size			|in KBytes (0 to 640)
40:15 %04.4x	RESERVED			|
40:17 %02.2x	Keyboard control 1		!
      x.......	|insert mode active
      .x......	|caps lock mode active
      ..x.....	|num lock mode active
      ...x....	|scroll lock mode active
      ....x...	|alt key held down
      .....x..	|ctrl key held down
      ......x.	|left shift key held down
      .......x	|right shift key held down
40:18 %02.2x	Keyboard control 1		!
      x.......	|insert key held down
      .x......	|caps lock key held down
      ..x.....	|num lock key held down
      ...x....	|scroll lock key held down
      ....x...	|pause mode active
      .....x..	|system request key held down
      ......x.	|left alt key held down
      .......x	|right ctrl key held down
40:19 %02.2x	Alternate keypad entry		|
40:1A %04.4x	Keyboard buffer head pointer	|p.to first ch.in typeahead buf
40:1C %04.4x	Keyboard buffer tail pointer	|p.to last ch.in typeahead buf
40:1E 32%02.2x	Keyboard buffer			|
40:3E %02.2x	Floppy recalibrate status	!
      x.......	|interrupt flag
      .xxx....	|reserved
      ....x...	|recalibrate drive 3
      .....x..	|recalibrate drive 2
      ......x.	|recalibrate drive 1
      .......x	|recalibrate drive 0
40:3F %02.2x	Floppy morter status		!
      x.......	|write/read operation
      .x......	|reserved
      ..xx....	|drive select (binary value equals drive number)
      ....x...	|drive 3 moter ON status
      .....x..	|drive 2 moter ON status
      ......x.	|drive 1 moter ON status
      .......x	|drive 0 moter ON status
40:40 %02.2x	Moter off counter		|
40:41 %02.2x	Floppy previous operation status!
     =10000000	|drive not ready
     =01000000	|seek operation faild
     =00100000	|general controller faild
     =00010000	|CRC error on diskette read
     =00001000	|DMA overrun on operation
     =00000100	|requested sector not found
     =00000010	|address mask not found
     =00000001	|invalid drive parameter
     =00000000	|no error
     =00000011	|write-protect error
     =00000110	|disk changed
     =00001001	|DMA attempt access 64K segment boundary
     =00001100	|media type not found
40:42 7%02.2x	Floppy controller status byte	|
40:49 %02.2x	Display mode			|
40:4A %04.4x	Number of columns		|
40:4C %04.4x	Length of regen buffer in bytes	|
40:4E %04.4x	Address of regen buffer		|
40:50 %04.4x	Cursor position page 1		|
40:52 %04.4x	Cursor position page 2		|
40:54 %04.4x	Cursor position page 3		|
40:56 %04.4x	Cursor position page 4		|
40:58 %04.4x	Cursor position page 5		|
40:5A %04.4x	Cursor position page 6		|
40:5C %04.4x	Cursor position page 7		|
40:5D %04.4x	Cursor position page 8		|
40:60 %04.4x	Cursor type			|
40:62 %02.2x	Current display page		|
40:63 %04.4x	Video controller base address	|
40:65 %02.2x	Current 3x8 register setting	|
40:66 %02.2x	Current 3x9 register setting	|
40:67 %08.8lx	Pointer to reset code		|PS/2 only
40:6B %02.2x	RESERVED			|
40:6C %08.8lx	Timer counter			|
40:70 %02.2x	Timer overflow flag		|!=0 passed 24 hours
40:71 %02.2x	Break key state			|
40:72 %04.4x	Reset flag			#
     =1234H	|bypass mem test
     =4321H	|preserve mem (PS/2)
     =5678H	|system suspended (Cobvertible)
     =9ABCH	|mfg test (Cobvertible)
     =ABCDH	|system post loop (Convertible only)
40:74 %02.2x	Fixed disk previous ope.status	#
     =00H	|[F&H] no error
     =01H	|[F&H] invalid diskette parameter (bad command)
     =02H	|[F&H] address mark was not found
     =03H	|[FDD] attempted write on protected diskette
     =04H	|[F&H] sector was not found
     =05H	|[FDD] reset failed
     =06H	|[FDD] diskette was removed
     =07H	|[HDD] bad parameter table
     =08H	|[FDD] DMA overrun on previous operation
     =09H	|[F&H] attempted to croo 64K segment boundary on DMA operation
     =0AH	|[HDD] bad sector flag
     =0BH	|[HDD] bad cylinder detected
     =0CH	|[FDD] media type requested was not found
     =0DH	|[HDD] invalid number of sectors in format
     =0EH	|[HDD] control data address mark detected
     =0FH	|[HDD] DMA arbitration level out of allowable range
     =10H	|[F&H] CRC or ECC error on disk read
     =11H	|[HDD] ECC corrected data error
     =20H	|[F&H] controller faild
     =40H	|[F&H] seek operation faild
     =80H	|[F&H] drive time out, assumed not ready
     =AAH	|[HDD] drive not ready
     =BBH	|[HDD] undefined error
     =CCH	|[HDD] write fault
     =E0H	|[HDD] status error
     =FFH	|[HDD] sense operation faild
40:75 %02.2x	Number of fixed drives		|
40:76 %02.2x	Fixed disk drive control	|XT only
40:77 %02.2x	Fixed disk controller port	|XT only
40:78 %02.2x	Printer 1 time-out value	|
40:79 %02.2x	Printer 2 time-out value	|
40:7A %02.2x	Printer 3 time-out value	|
40:7B %02.2x	Printer 4 time-out value	|PC,XT,and AT only
40:7C %02.2x	COM1 time-out value		|
40:7D %02.2x	COM2 time-out value		|
40:7E %02.2x	COM3 time-out value		|
40:7F %02.2x	COM4 time-out value		|
40:80 %04.4x	Keyboard buffer start offset ptr|
40:82 %04.4x	Keyboard buffer end offset ptr	|
40:84 %02.2x	Video rows (minus one)		|
40:85 %04.4x	Charactor height (bytes/char)	|
40:87 %02.2x	Video controll states 1		|
40:88 %02.2x	Video controll states 2		|
40:89 %04.4x	RESERVED			|
40:8B %02.2x	Media control			!
     =00......	|last floppy drive data rate (500KB/sec.)
     =01......	|last floppy drive data rate (300KB/sec.)
     =10......	|last floppy drive data rate (250KB/sec.)
     =11......	|last floppy drive data rate (reserved)
      ..xx....	|last floppy drive step rate
      ....xxxx	|reserved
40:8C %02.2x	Fixed disk controller status	|
40:8D %02.2x	Fixed disk controller error sta.|
40:8E %02.2x	Fixed disk interrupt control	|
40:8F %02.2x	RESERVED			|
40:90 %02.2x	Drive 0 media status		!
     =00......	|drive data rate (500KB/sec.)
     =01......	|drive data rate (300KB/sec.)
     =10......	|drive data rate (250KB/sec.)
     =11......	|drive data rate (reserved)
      ..x.....	|double steppind required
      ...x....	|media established
      ....x...	|reserved
      .....xxx	|drive/media state
40:91 %02.2x	Drive 1 media status		!
     =00......	|drive data rate (500KB/sec.)
     =01......	|drive data rate (300KB/sec.)
     =10......	|drive data rate (250KB/sec.)
     =11......	|drive data rate (reserved)
      ..x.....	|double steppind required
      ...x....	|media established
      ....x...	|reserved
      .....xxx	|drive/media state
40:92 %04.4x	RESERVED			|
40:94 %02.2x	Drive 0 current cylinder	|
40:95 %02.2x	Drive 1 current cylinder	|
40:96 %02.2x	Keyboard mode state, type flag	!
      x.......	|read ID in progress
      .x......	|last character was first ID character
      ..x.....	|force num lock if read ID and KBX
      ...x....	|101/102-key keyboard installed
      ....x...	|right alt key held down
      .....x..	|right ctrl key held down
      ......x.	|last code was E0 hidded code
      .......x	|last code was E1 hidden code
40:97 %02.2x	Keyboard LED flags		!
      x.......	|keyboard transmit error flag
      .x......	|mode indicator update
      ..x.....	|resend receive flag
      ...x....	|acknowledgement received
      ....x...	|reserved
      .....xxx	|LED state bits
40:98 %04.4x	Off.addr.to user wait cmplt. flg|
40:9A %04.4x	Seg.addr.to user wait complete	|
40:9C %04.4x	User wait count (low word)	|in microseconds
40:9E %04.4x	User wait count (high word)	|in microseconds
40:A0 %02.2x	Wait active flag		!
      x.......	|wait time elapsed and post
      .xxxxxx.	|reserved
      .......x	|int 15H function 86H (wait) has occurred
40:A1 7%02.2x	RESERVED			|
40:A8 %08.8lx	Video parameter table pointer	|EGA and PS/2 only
40:AC %08.8lx	Dynamic save area pointer	|EGA and PS/2 only
40:B0 %08.8lx	Alpha mode aux char gen pointer	|EGA and PS/2 only
40:B4 %08.8lx	Graphics mode aux char gen ptr.	|EGA and PS/2 only
40:B8 %08.8lx	Secondary save pointer		|EGA and PS/2 only
40:BC 8%02.2x	RESERVED			|
40:C0 64%02.2x	RESERVED			|
50:00 %02.2x	Print screen status byte	|
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