PORTIBM PC Portable (uses same BIOS as XT) 0070-007F - CMOS RAMA small amount (typically 64 or 128 bytes) of memory in the system's real-time clock chip that is preserved by the clock's battery and is used for storing configuration information.  See also Real-Time Clock./RTCsee Real-Time Clock (REAL TIME CLOCK)
Note:	the real-time clock may be either a discrete MC146814, MC146818, or
	  an emulation thereof built into the motherboard chipset
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 00A0h"XTIBM PC XT"

0070  -W  CMOS RAMA small amount (typically 64 or 128 bytes) of memory in the system's real-time clock chip that is preserved by the clock's battery and is used for storing configuration information.  See also Real-Time Clock. index register port (ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA., EISA(Enhanced Industry-Standard Architecture) A 32-bit superset of the IBMInternational Busiuness Machines ATIBM PC AT's expansion bus (which is now known as the ISA or Industry-Standard Architecture bus).)
		 bit 7	= 1  NMIsee Non-Maskable Interrupt disabled from reaching CPU(Central Processing Unit) The microprocessor which executes programs on your computer.
			= 0  NMIsee Non-Maskable Interrupt enabled
		 bit 6-0     CMOS RAMA small amount (typically 64 or 128 bytes) of memory in the system's real-time clock chip that is preserved by the clock's battery and is used for storing configuration information.  See also Real-Time Clock. index
			(64 bytes in early systems, now usually 128 bytes)
	Note:	any write to PORTIBM PC Portable (uses same BIOS as XT) 0070h should be followed by an action to
		  PORTIBM PC Portable (uses same BIOS as XT) 0071h or the RTCsee Real-Time Clock wil be left in an unknown state.
0071  RW  CMOS RAMA small amount (typically 64 or 128 bytes) of memory in the system's real-time clock chip that is preserved by the clock's battery and is used for storing configuration information.  See also Real-Time Clock. data port (ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA., EISA(Enhanced Industry-Standard Architecture) A 32-bit superset of the IBMInternational Busiuness Machines ATIBM PC AT's expansion bus (which is now known as the ISA or Industry-Standard Architecture bus).) (see #P0409)


(Table P0409)
Values for Real-Time ClockA battery-powered clock which continues to maintain its time even while the system is powered down.  On PCs, the real-time clock contains a small amount of battery-powered memory (set CMOS RAM). register number (see also CMOS(Complementary Metal-Oxide-Semiconductor) A type of integrated circuit design known for its low power consumption..LST):
 00h-0Dh clock registers
 0Eh	diagnostics status byte
 0Fh	shutdown status byte
 10h	diskette drive type for A: and B:
 11h	reserved / IBMInternational Busiuness MachinesInternational Busiuness Machines) A hardware, software and other service technology company founded in 1911. fixed disk / setup options
 12h	fixed disk drive type for drive 0 and drive 1
 13h	reserved / AMIAmerican Megatrends, Inc.(American Megatrends, Inc.) A hardware, software and firmware company founded in 1985. Extended CMOS(Complementary Metal-Oxide-Semiconductor) A type of integrated circuit design known for its low power consumption. setup (AMIAmerican Megatrends, Inc.(American Megatrends, Inc.) A hardware, software and firmware company founded in 1985. Hi-Flex BIOS(Basic Input/Output System) A set of standardized calls giving low-level access to the hardware.  The BIOS is the lowest software layer above the actual hardware and serves to insulate programs (and operating systems) which use it from the details of accessing the hardware directly.)
 14h	equipment byte
 15h	LSB of system base memory in Kb
 16h	MSB of system base memory in Kb
 17h	LSB of total extended memory in Kb
 18h	MSB of total extended memory in Kb
 19h	drive C extension byte
 1Ah	drive D extension byte
 1Bh-2Dh reserved
 20h-27h commonly used for first user-configurable drive type
 2Eh	CMOS(Complementary Metal-Oxide-Semiconductor) A type of integrated circuit design known for its low power consumption. MSB checksum over 10-2D
 2Fh	CMOS(Complementary Metal-Oxide-Semiconductor) A type of integrated circuit design known for its low power consumption. LSB checksum over 10-2D
 30h	LSB of extended memory found above 1Mb at POSTsee Power-On Self-Test
 31h	MSB of extended memory found above 1Mb at POSTsee Power-On Self-Test
 32h	date century in BCD(Binary Coded Decimal) A method of data storage where two decimal digits are stored in each byte, one in the upper four bits and the other in the lower four bits.  Since only the values 0 through 9 are used in each half of a byte, BCD values can be read as decimal numbers on a hexadecimal display of memory or a file.
 33h	information flags
 34h-3Fh	reserved
 35h-3Ch commonly used for second user-configurable drive type
 3Dh-3Eh word to 82335 MCR memory config register at [22] (Phoenix)
 42h-4Ch AMIAmerican Megatrends, Inc.(American Megatrends, Inc.) A hardware, software and firmware company founded in 1985. 1990 Hyundai super-NB368S notebook
	???
 54h-57h AMIAmerican Megatrends, Inc.(American Megatrends, Inc.) A hardware, software and firmware company founded in 1985. 1990 Hyundai super-NB368S notebook
	???
 5Ch-5Dh AMIAmerican Megatrends, Inc.(American Megatrends, Inc.) A hardware, software and firmware company founded in 1985. 1990 Hyundai super-NB368S notebook
	???
 60h-61h AMIAmerican Megatrends, Inc.(American Megatrends, Inc.) A hardware, software and firmware company founded in 1985. 1990 Hyundai super-NB368S notebook
	???