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devn-micrel8841.so
Driver for Micrel 8841 (1 port) or 8842 (2 port) Ethernet controllers
Syntax:
io-pkt-variant -d micrel8841 [option[,option ...]] ... &
where variant is one of v4, v4-hc, or v6-hc.
Runs on:
Neutrino
Options:
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Use commas, not spaces, to separate the options. |
- did=0xXXXX
- The PCI device ID.
- duplex=0|1
- Half (0) or full (1) duplex mode. The default is automatically detected on supported hardware. If you specify duplex, specify speed as well; if duplex alone is specified, it is ignored and both speed and duplex are autonegotiated.
- multicast
- Enable the receipt of all multicast packets, all ports. By default, the receipt of multicast packets is disabled.
- pci=0xXXXX
- The PCI index of the controller.
- port0=num
- 1 means power down port 0 PHY (the default is 0, power on).
- port1=num
- 1 means power down port 1 PHY (the default is 0, power on) on the 8842 (2 port).
- priority=N
- The priority of the driver's event thread. The default is 21.
- promiscuous
- Allow the driver to pass all data packets received, regardless of the address. By default, promiscuous mode is disabled.
- receive=num
- The number of Rx descriptors (and 2 KB npkts) to allocate. The default is 256.
- speed=10|100
- Set the link speed (specified in Mbits/second: 10 or 100).
- switch
- Enable switch mode on the 2-port 8842.

This is very dangerous if you loop the network because of the resulting packet storms. - transmit=num
- The number of Tx descriptors to allocate (the default is 256).
- verbose
verbose=N - Be verbose. Specify num for more verbosity (num can be 1-4; the higher the number, the more detailed the output). The default is 0. The output goes to slogger; invoke sloginfo to view it.
- vid=0xXXXX
- The PCI vendor ID.
Description:
The devn-micrel8841.so driver controls Micrel 8841 (1 port) or 8842 (2 port) Ethernet controllers. This is a legacy io-net driver; its interface names are in the form enX, where X is an integer.
This driver supports hardware checksum calculations for both Tx and Rx of IP and TCP packets (UDP isn't supported). To enable hardware checksumming, use ifconfig like this, after starting the driver:
ifconfig enX ip4csum tcp4csum
Examples:
Start io-pkt-v6-hc using the devn-micrel8841.so driver and Qnet with 1024 transmit descriptors, and 1024 receive descriptors to avoid packet loss due to scheduling latency on slow processors:
io-pkt-v6-hc -d micrel8841 transmit=1024,receive=1024 -p qnet
Files:
- /dev/io-net
- The directory where, by default, drivers and protocol modules add entries. For more information, see the documentation for io-pkt*.
See also:
devn-*, devnp-*, ifconfig, io-pkt*
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