TXP(4) BSD Kernel Interfaces Manual TXP(4)
txp -- 3Com 3XP Typhoon/Sidewinder (3CR990) Ethernet interface
The txp interface provides access to the 10Mb/s and 100Mb/s Ethernet net-
works via the 3Com Typhoon/Sidewinder chipset.
Basic Ethernet functions are provided as well as support for vlan(4) tag
removal and insertion assistance, receive ip(4), tcp(4), and udp(4)
checksum offloading, and transmit ip(4) checksum offloading. There is
currently no support for transmit tcp(4) or udp(4) checksum offloading,
tcp(4) segmentation, nor ipsec(4) acceleration. Note that hardware
checksumming is only used when the interface is not in bridge(4) mode.
Each of the host's network addresses is specified at boot time with an
SIOCSIFADDR ioctl(2). The txp interface employs the address resolution
protocol described in arp(4) to dynamically map between Internet and Eth-
ernet addresses on the local network.
When a txp interface is brought up, by default, it will attempt to auto-
negotiate the link speed and duplex mode. The speeds, in order of
attempt, are: 100Mb/s Full Duplex, 100Mb/s Half Duplex, 10 Mb/s Full
Duplex, and 10 Mb/s Half Duplex.
The txp supports several media types, which are selected via the
ifconfig(8) command. The supported media types are:
Attempt to autoselect the media type (default)
media 100baseTX mediaopt full-duplex
Use 100baseTX, full duplex
media 100baseTX [mediaopt half-duplex]
Use 100baseTX, half duplex
media 10baseT mediaopt full-duplex
Use 10baseT, full duplex
media 10baseT [mediaopt half-duplex]
Use 10baseT, half duplex
The txp driver supports the following cards:
o 3Com 3CR990-TX-95
o 3Com 3CR990-TX-97
o 3Com 3cR990B-TXM
o 3Com 3CR990SVR95
o 3Com 3CR990SVR97
o 3Com 3cR990B-SRV
arp(4), inet(4), intro(4), ip(4), miibus(4), tcp(4), udp(4), vlan(4),
The txp driver first appeared in OpenBSD 2.9.
BSD July 4, 2004 BSD