PORTIBM PC Portable (uses same BIOS as XT) 0300-031F - 3com Ethernet adapters (default address)
                                                                                

PORTIBM PC Portable (uses same BIOS as XT) 0300-031F - NE2000 compatible Ethernet adapters
Range:	may be placed at 0300h, 0320h, 0340h, or 0360h
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 0300h"PCnet"
                                                                                


PORTIBM PC Portable (uses same BIOS as XT) 0300-031F - AMD PCnet - NE2100-compatible Ethernet adapters
Range:	may be placed at 0300h, 0320h, 0340h, or 0360h, with the card's ROM(Read-Only Memory) A memory for program storage which may not be changed by the program as it runs.
	  appearing at segment C800h, CC00h, D000h, or D400h, respectively
Note:	for the PCnet-FAST chip, the I/O address may be read from the PCI
	  configuration space at offset 10h (see #00878 at INT 1A/AX=B10Ah)
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 0300h"NE2000",#00878

0300-030F  R-  address PROM (used to store Ethernet address, etc.)
0310w RW  Register Data Port (RDP) (see #P0552,#P0553)
0312w ?W  Register Access Port (RAP) (selects register index for RDP and IDP)
	  (see #P0570)
0314w ?W  Reset
0316w RW  ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA. Bus Data Port (IDP)
0318w	  reserved for vendor-specific use
031A-031F      reserved


(Table P0552)
Values for AMD PCnet-ISA Register Data Port index:
 00h	"CSR0" status and control flags (see #P0554)
 01h	"CSR1" low half of IADR (appears at PORTIBM PC Portable (uses same BIOS as XT) 0316h)
 02h	"CSR2" high half of IADR (appears at PORTIBM PC Portable (uses same BIOS as XT) 0317h)
 03h	"CSR3" interrupt masks (see #P0555)
 04h	"CSR4" interrupt masks and status bits (see #P0556)
 08h-0Bh logical address filter
 0Ch-0Eh physical address register
 0Fh	"CSR15" mode (see #P0560)
 4Ch	"CSR76" receive descriptor ring length
 4Eh	"CSR78" transmit descriptor ring length
 50h	"CSR80" FIFO threshold / DMAsee Direct Memory Access burst control (see #P0564)
 52h	"CSR82" DMAsee Direct Memory Access bus timer
 58h	"CSR88" chip ID
 70h	"CSR112" number of missed packets
 72h	"CSR114" number of receive collisions
 7Ch	"CSR124" BMU test register
		bit 4: accept runt packets
SeeAlso: #P0570,#P0553


(Table P0553)
Values for AMD PCnet-SCSI/PCnet-FAST Register Data Port index:
 00h	"CSR0" status and control flags (see #P0554)
 01h	"CSR1" low half of IADR (appears at PORTIBM PC Portable (uses same BIOS as XT) 0316h)
 02h	"CSR2" high half of IADR (appears at PORTIBM PC Portable (uses same BIOS as XT) 0317h)
 03h	"CSR3" interrupt masks (see #P0555)
 04h	"CSR4" interrupt masks and status bits (see #P0556)
 05h	"CSR5" (PCnet-FAST) extended control and interrupt 1 (see #P0557)
 06h	"CSR6" receive/transmit descriptor table lengths (see #P0558)
 07h	"CSR7" (PCnet-FAST) extended control and interrupt 2 (see #P0559)
 08h-0Bh logical address filter
 0Ch-0Eh physical address register
 0Fh	"CSR15" mode (see #P0560)
 10h	"CSR16"	alias of CSR1
 11h	"CSR17"	alias of CSR2
 12h	"CSR18" low half of current receive buffer address
 13h	"CSR19" high half of current receive buffer address
 14h	"CSR20" low half of current transmit buffer address
 15h	"CSR21" high half of current transmit buffer address
 16h	"CSR22" low half of next receive buffer address
 17h	"CSR23" high half of next receive buffer address
 18h	"CSR24" low half of receive-ring base address
 19h	"CSR25" high half of receive-ring base address
 1Ah	"CSR26" low half of next receive descriptor address
 1Bh	"CSR27" high half of next receive descriptor address
 1Ch	"CSR28" low half of current receive descriptor address
 1Dh	"CSR29" high half of current receive descriptor address
 1Eh	"CSR30" low half of transmit ring base address
 1Fh	"CSR31" high half of transmit ring base address
 20h	"CSR32" low half of next transmit descriptor address
 21h	"CSR33" high half of next transmit descriptor address
 22h	"CSR34" low half of current transmit descriptor address
 23h	"CSR35" high half of current transmit descriptor address
 24h	"CSR36" low half of next next receive descriptor address
 25h	"CSR37" high half of next next receive descriptor address
 26h	"CSR38" low half of next next transmit descriptor address
 27h	"CSR39" high half of next next transmit descriptor address
 28h	"CSR40" current receive byte count (see #P0561)
 29h	"CSR41" current receive status
 2Ah	"CSR42" current transmit byte count (see #P0562)
 2Bh	"CSR43" current transmit status
 2Ch	"CSR44" next receive byte count (bits 11-0; bits 15-12=0)
 2Dh	"CSR45" next receive status
 2Eh	"CSR46" transmit poll time counter
 2Fh	"CSR47" transmit polling interval
 30h	"CSR48" receive poll time counter
 31h	"CSR49" receive polling interval
 32h-39h reserved
 3Ah	"CSR58" software style (see #P0563)
 3Bh	reserved
 3Ch	"CSR60" previous transmit descriptor address (low)
 3Dh	"CSR61" previous transmit descriptor address (high)
 3Eh	"CSR62" previous transmit byte count (bits 11-0; bits 15-12=0)
 3Fh	"CSR63" previous transmit status
 40h	"CSR64" next transmit buffer address (low)
 41h	"CSR65" next transmit buffer address (high)
 42h	"CSR66" next transmit byte count (bits 11-0; bits 15-12=0)
 43h	"CSR67" next transmit status
 44h-47h reserved
 48h	"CSR72" receive ring counter
 49h	reserved
 4Ah	"CSR74" transmit ring counter
 4Bh	reserved
 4Ch	"CSR76" receive descriptor ring length
 4Dh	reserved
 4Eh	"CSR78" transmit descriptor ring length
 4Fh	reserved
 50h	"CSR80" FIFO threshold / DMAsee Direct Memory Access burst control (see #P0564)
 51h	reserved
 52h	"CSR82" (PCnet-SCSI) DMAsee Direct Memory Access bus timer
		(PCnet-FAST) transmit descriptor address (low)
 53h	reserved
 54h	"CSR84" DMAsee Direct Memory Access address register (low)
 55h	"CSR85" DMAsee Direct Memory Access address register (high)
 56h	"CSR86" buffer byte counter (bits 11-0; bits 15-12=0)
 57h	reserved
 58h	"CSR88" chip ID (low 16 bits) (see #P0565)
 59h	"CSR89" chip ID (high 16 bits) (see #P0565)
 5Ah	"CSR90" (PCnet-SCSI)
 5Bh	reserved
 5Ch	"CSR92" ring length conversion
 5Dh	reserved
 5Eh	"CSR94" (PCnet-SCSI)
 5Fh-63h reserved
 64h	"CSR100" bus timeout
 65h-6Fh reserved
 70h	"CSR112" number of missed packets
 71h	reserved
 72h	"CSR114" number of receive collisions
 73h-79h reserved
 7Ah	"CSR122" advanced feature control (see #P0566)
 7Bh	reserved
 7Ch	"CSR124" BMU test register (see #P0567)
 7Dh	"CSR125" (PCnet-FAST) MAC Enhanced Configuration Control (see #P0568)
 7Eh-7Fh reserved
SeeAlso: #P0552,#P0594


Bitfields for AMD PCnet CSR0 status and control flags:
Bit(s)	Description	(Table P0554)
 15	"ERR"	error; set if BABL, CERR, MISS, or MESS set
 14	"BABL"	network babbling control
 13	"CERR"	collision error
 12	"MISS"	missed frame
 11	"MERR"	memory error
 10	"RINT"	receive interrupt
 9	"TINT"	transmit interrupt
 8	"IDON"	initialization done
 7	"INTR"	interrupt flag
 6	"IENA"	interrupt enable
 5	"RXON"	recieve ON
 4	"TXON"	transmit ON
 3	"TDMD"	transmit demand
 2	"STOP"	stop -- disable all external activity
 1	"STRT"	start -- enable extrnal activity
 0	"INIT"	begin initialization procedure
SeeAlso: #P0552,#P0555


Bitfields for AMD PCnet CSR3 interrupt masks:
Bit(s)	Description	(Table P0555)
 15	reserved
 14	"BABLM"	disable babble interrupt
 13	reserved
 12	"MISSM" disable missed-frame interrupt
 11	"MERM"	disable memory-error interrupt
 10	"RINTM"	disable receive interrupt
 9	"TINTM" disable transmit interrupt
 8	"IDONM" disable initialization-done interrupt
 7-5	reserved
 4	"DXMT2PD" disable Transmit Two Part Deferral
 3	"EMBA"	enable modified back-off algorithm
 2-0	reserved
Note:	other bits are reserved
SeeAlso: #P0552,#P0554,#P0556


Bitfields for AMD PCnet CSR4 interrupt masks and status bits:
Bit(s)	Description	(Table P0556)
 15	"ENTST"	   enable Test Mode / CSR124 access
 14	"DMAPLUS"  disable CSR80 burst transaction counter
 13	"TIMER"	   enable Bus Timer register
 12	"DPOLL"	   disable transmit polling
 11	"APADXMT"  Auto-Pad Transmit
 10	"ASTRPRCV" enable automatic pad stripping
 9	"MFCO"	   missed frame counter has overflowed
 8	"MFCOM"	   disable interrupt on MFCO
 7	"UINTCMD"  (PCnet-FAST) user interrupt command
 6	"UINT"	   (PCnet-FAST) user interrupt pending
			write 1 to clear
 5	"RCVCCO"   receive collision counter has overflowed
 4	"RCVCCOM"  disable interrupt on RCVCCO
 3	"TXSTRT"   Transmit Start
 2	"TXSTRTM"  disable interrupt on TXSTRT
 1	"JAB"	   Jabber error
 0	"JABM"	   disable interrupt on JAB
SeeAlso: #P0552,#P0555,#P0553


Bitfields for AMD PCnet-FAST CSR5 extended control and interrupt 1:
Bit(s)	Description	(Table P0557)
 31-16	reserved
 15	"TOKINTD"  disable Transmit OK interrupt
 14	"LTINTEN"  enable Last Transmit interrupt
 13-12	reserved
 11	"SINT"	   System Interrupt (write 1 to clear)
 10	"SINTE"	   enable System Interrupt
 9	"SLPINT"   Sleep Interrupt (write 1 to clear)
 8	"SLPINTE"  enable Sleep Interrupt
 7	"EXDINT"   Excessive Deferral Interrupt (write 1 to clear)
 6	"EXDINTE"  enable Excessive Deferral Interrupt
 5	"MPPLBA"   Magic Packet Physical Logical Broadcast Accept
 4	"MPINT"	   Magic Packet Interrupt (write 1 to clear)
 3	"MPINTE"   enable Magic Packet Interrupt
 2	"MPEN"	   enable Magic Packet mode
 1	"MPMODE"   Magic Packet mode active
 0	"SPND"	   Suspend
SeeAlso: #P0553,#P0556,#P0559


Bitfields for AMD PCnet CSR6 Descriptor Table Length register:
Bit(s)	Description	(Table P0558)
 15-12	transmit encoded ring length
 11-8	receive encoded ring length
 7-0	reserved
SeeAlso: #P0553,#P0557


Bitfields for AMD PCnet CSR7 Extended Control and Interrupt 2:
Bit(s)	Description	(Table P0559)
 15	"FASTSPNDE"  enable Fast Suspend
 14	"RXFRTG"     Receive Frame Tag
 13	"RDMD"	     Receive Demand
 12	"RXDPOL"     disable receive polling
 11	"STINT"	     Software Timer Interrupt (write 1 to clear)
 10	"STINTE"     enable Software Timer Interrupt
 9	"MREINT"     MII Management Read Error Interrupt (write 1 to clear)
 8	"MREINTE"    enable MII Management Read Error Interrupt
 7	"MAPINT"     MII Management Auto-Poll Interrupt (write 1 to clear)
 6	"MAPINTE"    enable MII Management Auto-Poll Interrupt
 5	"MCCINT"     MII Management Command Complete Interrupt (write 1 to clr)
 4	"MCCINTE"    enable MII Management Command Complete Interrupt
 3	"MCCIINT"    MII Management Command Complete Internal Interrupt
			(write 1 to clear)
 2	"MCCIINTE"   enable MII Manamagement Command Complete Internal Int.
 1	"MIIPDTINT"  MII PHY Detect Transition Interrupt (write 1 to clear)
 0	"MIIPDTINTE" enable MII PHY Detect Transition Interrupt
SeeAlso: #P0553,#P0557


Bitfields for AMD PCnet CSR15 mode flags:
Bit(s)	Description	(Table P0560)
 15	"PROM"	   promiscuous mode
 14	"DRCVBC"   disable Receive Broadcast
 13	"DRCVPA"   disable Receive Physical Address
 12	"DLNKTST"  disable Link Status
 11	"DAPC"	   disable Automatic Polarity Correction
 10	"MENDECL"  MENDEC loopback mode
 9	"LRT/TSEL" Low Receive Threshold
 8-7	"PORTSEL"  Port Select
		00  AUI
		01  10Base-T
		10  GPSI
		11  reserved
 6	"INTL"	   internal loopback
 5	"DRTY"	   disable retry
 4	"FCOLL"	   force collision
 3	"DXMTFCS"  disable Transmit CRC
 2	"LOOP"	   enable Loopback
 1	"DTX"	   disable transmitter
 0	"DRX"	   disable receiver
SeeAlso: #P0552,#P0556,#P0564


Bitfields for AMD PCnet CSR40 Current Receive Byte Count register:
Bit(s)	Description	(Table P0561)
 15-12	reserved (0)
 11-0	current receive byte count (copy of BCNT field of current receive
	  descriptor's RMD1)
SeeAlso: #P0553,#P0562


Bitfields for AMD PCnet CSR42 Current Transmit Byte Count register:
Bit(s)	Description	(Table P0562)
 15-12	reserved (0)
 11-0	current transmit byte count (copy of BCNT field of current receive
	  descriptor's TMD1)
SeeAlso: #P0553,#P0561


Bitfields for AMD PCnet CSR58 Software Style register:
Bit(s)	Description	(Table P0563)
 15-11	reserved (undefined)
 10	"APERREN"	enabled advanced parity error handling
 9	"CSRPCNET"	PCnet-ISA compatibility (read-only)
 8	"SSIZE32"	32-bit software structures for data blocks
 7-0	"SWSTYLE"	software style
		00h LANCE/PCnet-ISA (16-bit software structures)
		01h reserved
		02h PCnet-PCI (32-bit software)
		03h PCnet-PCI (32-bit software)
SeeAlso: #P0553


Bitfields for AMD PCnet CSR80 FIFO threshold and DMAsee Direct Memory Access burst control:
Bit(s)	Description	(Table P0564)
 15-14	reserved
 13-12	receive FIFO high-water mark; request DMAsee Direct Memory Access when N byte available
	00 = 16 bytes
	01 = 32 bytes
	10 = 64 bytes
 11-10	transmit starting point; start transmission after N bytes written
	00 = 4 bytes
	01 = 16 bytes
	10 = 64 bytes
	11 = 112 bytes
 9-8	transmit FIFO low-water mark; start DMAsee Direct Memory Access when room for N bytes
	00 = 8 bytes
	01 = 16 bytes
	10 = 32 bytes
 7-0	DMAsee Direct Memory Access burst register
SeeAlso: #P0552,#P0560


Bitfields for AMD PCnet Chip ID register (read-only):
Bit(s)	Description	(Table P0565)
 31-28	hardware version
 27-12	part number
	2623h = Am79C971
 11-1	manufacturer ID (0001h = AMD)
 0	reserved (1)
SeeAlso: #P0553


Bitfields for AMD PCnet CSR122 Advanced Feature Control register:
Bit(s)	Description	(Table P0566)
 15-1	reserved
 0	"RCVALGN"	DWORD-align received packets
SeeAlso: #P0553,#P0567


Bitfields for AMD PCnet CSR124 Test Register 1:
Bit(s)	Description	(Table P0567)
 15-5	reserved
 4	(PCnet-SCSI) accept runt packets
 3	(PCnet-FAST) accept runt packets
 2-0	reserved
SeeAlso: #P0553,#P0566


Bitfields for AMD PCnet-FAST CSR125 MAC Enhanced Configuration Control reg:
Bit(s)	Description	(Table P0568)
 15-8	inter-packet gap (reducing from default 96 can disrupt network)
 7-0	inter-frame spacing, part 1
SeeAlso: #P0553


(Table P0569)
Values for AMD PCnet-ISA ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA. Bus Configuration Register index:
 00h	"MSRDA" width of DMAsee Direct Memory Access read signal
 01h	"MSWRA" width of DMAsee Direct Memory Access write signal
 02h	"MC"	ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA. bus configuration (see #P0572)
 05h	"LED1"	LED1 signal control (see #P0573)
 06h	"LED2"	LED2 signal control (see #P0573)
 07h	"LED3"	LED3 signal control (see #P0573)
SeeAlso: #P0552,#P0594,#P0570


(Table P0570)
Values for AMD PCnet-SCSI Bus Configuration Register index:
 00h	"MSRDA" width of DMAsee Direct Memory Access read signal (reserved)
 01h	"MSWRA" width of DMAsee Direct Memory Access write signal (reserved)
 02h	"MC"	miscellaneous configuration (see #P0572)
 03h	reserved
 04h	"LINKST" link status
 05h	"LED1"	LED1 signal control (see #P0573) -- receive status
 06h	"LED2"	LED2 signal control (see #P0573)
 07h	"LED3"	LED3 signal control (see #P0573) -- transmit status
 08h-0Fh reserved
 10h	"IOBASEL"
 11h	"IOBASEU"
 12h	"BSBC"	burst size and bus control
 13h	"EECAS" EEPROM Control and Status
 14h	"SWS"	software style
 15h	"INTCON" reserved
SeeAlso: #P0553,#P0569,#P0571


(Table P0571)
Values for AMD PCnet-FAST Bus Configuration Register index:
 00h	"MSRDA"		width of DMAsee Direct Memory Access read signal (reserved)
 01h	"MSWRA"		width of DMAsee Direct Memory Access write signal (reserved)
 02h	"MC"		miscellaneous configuration (see #P0572)
 03h	reserved	!!!p.154
 04h	"LED0"	LED0 status
 05h	"LED1"	LED1 signal control (see #P0573) -- receive status
 06h	"LED2"	LED2 signal control (see #P0573)
 07h	"LED3"	LED3 signal control (see #P0573) -- transmit status
 08h	reserved
 09h	"FDC"		full-duplex control
 0Ah-0Fh reserved
 10h	"IOBASEL"	I/O base select (lo) -- reserved
 11h	"IOBASEU"	I/O base select (hi) -- reserved
 12h	"BSBC"		burst size and bus control
 13h	"EECAS"		EEPROM Control and Status
 14h	"SWS"		software style
 15h	"INTCON"	reserved
 16h	"PCILAT"	PCI-bus latency
 17h	"PCISID"	PCI subsystem ID
 18h	"PCISVID"	PCI subsystem vendor ID
 19h	"SRAMSIZ"	SRAM(Static Random Access Memory)  RAM which typically consists of one flip-flop per bit of memory.  Unlike DRAMs, static RAM retains its contents as long as power is applied.  Because there is no need to refresh the contents of memory addresses which are read, SRAM is faster than DRAM, but it is more expensive and typically is available in much smaller sizes than DRAM because each bit occupies more space on the chip.  See also DRAM. size
 1Ah	"SRAMB"		SRAM(Static Random Access Memory)  RAM which typically consists of one flip-flop per bit of memory.  Unlike DRAMs, static RAM retains its contents as long as power is applied.  Because there is no need to refresh the contents of memory addresses which are read, SRAM is faster than DRAM, but it is more expensive and typically is available in much smaller sizes than DRAM because each bit occupies more space on the chip.  See also DRAM. boundary
 1Bh	"SRAMIC"	SRAM(Static Random Access Memory)  RAM which typically consists of one flip-flop per bit of memory.  Unlike DRAMs, static RAM retains its contents as long as power is applied.  Because there is no need to refresh the contents of memory addresses which are read, SRAM is faster than DRAM, but it is more expensive and typically is available in much smaller sizes than DRAM because each bit occupies more space on the chip.  See also DRAM. interface control
 1Ch	"EBADDRL"	expansion bus address (low)
 1Dh	"EBADDRU"	expansion bus address (high)
 1Eh	"EBD"		expansion bus data port
 1Fh	"STVAL"		software timer value
 20h	"MIICAS"	MII control and status
 21h	"MIIADDR"	MII address
 22h	"MIIMDR"	MII management data
 23h	"PCIVID"	PCI vendor ID
SeeAlso: #P0553,#P0569,#P0570


Bitfields for AMD PCnet ISA(Industry-Standard Architecture) The expansion bus used by the IBMInternational Busiuness Machines PCIBM PC/ATIBM PC AT.  See also EISA. bus configuration:
Bit(s)	Description	(Table P0572)
 3	EADISEL
 2	AWAKE
 1	ASEL
 0	XMAUSEL
SeeAlso: #P0570,#P0573


Bitfields for AMD PCnet LEDn signal control:
Bit(s)	Description	(Table P0573)
 15	LEDOUT
 14-8	reserved
 7	PSE
 6-5	reserved
 4	XMTE
 3	RVPE
 2	RCVE
 1	JABE
 0	COLE
SeeAlso: #P0570