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Net.epic
SMC 83C170 Ethernet network driver (QNX)
Syntax:
Net.epic [-B] [-f tx_forget_time] [-F]
[-I pci_index] [-i irq]
[-l log_net_id] [-M]
[-n tx_num_retries] [-o] [-P]
[-p io_port] [-r media_rate]
[-s speed] [-t tx_retry_ticks] [-v] &
Options:
- -a io_port
- This option is no longer valid in QNX 4.25 and later. Use -p instead.
- -B
- Use the BNC (coax) port.
- -f tx_forget_time
- After a driver-level NACK is received from a remote node, Net.epic will assume that because packets were dropped, throttling the transmit output on that connection would be a good idea. So, the output will be reduced to approximately 400K/sec for 2 seconds, after which the eternally optimistic Net.epic stops throttling its output. The -f option allows you to change the default 2 seconds above.
- -F
- Force full-duplex operation of the card. The default is half-duplex unless the PHY auto-negotiates full-duplex.
- -I pci_index
- Have the driver look at this specific PCI Index for an epic-compatible card. You should have to specify -I only if you have more than one epic-compatible card installed (e.g. -I0, -I1, -I2).
- -i irq
- Program the card to use the specified hardware interrupt. This option overrides the default autodetect. If the autodetect doesn't work on an ISA card, you have a hardware conflict. This option should rarely be used.
- -l log_net_id
- ("el") Connect to the specified logical network. The default is 1.
- -M
- Program the NIC for multicast rx mode. All packets with multicast destination addresses will be buffered.
- -n tx_num_retries
- After failing to transmit to a remote node, retry transmission no more than this number of times. Default is 7.
- -o
- Use the fiber-optic port.
- -P
- Program the NIC for promiscuous receive mode. All
packets will be buffered, regardless of the
packet's destination address. The default
is non-promiscuous mode.
You may use this option in conjunction with netsniff to monitor other traffic on the network.
- -p io_port
- Use the given I/O port base, specified as a hexadecimal number without a leading 0x. This option overrides the default auto-detect, which uses the PCI BIOS to return a port address. In some earlier versions of QNX, the -p option was used to specify the PCI index. Use the -I option to specify the PCI Index of the card being used.
- -r media_rate
- Advertise the specified bit-transmission rate. The default is 100000000. This information is used by the Network Manager (Net) only when multiple network drivers are running.
- -s speed
- Set the speed at which the card should run. Only possible with 100Mbit cards. (e.g. -s10 or -s100) This disables the auto-negotiation capability of Ethernet card.
- -t tx_retry_ticks
- The number of 50 millisecond intervals between transmit retries. The default is 6.
- -v
- Be verbose; print out hardware configuration info on the screen when starting up.
Description:
The Net.epic network driver communicates with SMC's 83C170 PCI Ethernet adapter to provide the Network Manager with reliable data transfer over an Ethernet network. The driver supports PHY auto-negotiation with auto-negotiating partners. Auto-negotiation can be disabled by using the -s (speed) command-line option. Full-duplex operation can also be forced, using the -F option.
The driver lets you select a card's coax port using the -B option or a fiber-optic port using the -o option (for cards with LXT970 or Altima Phy interfaces).
Most of the time, you shouldn't need to specify the I/O port or the hardware interrupt to Net.epic -- it should autodetect these parameters from the PCI BIOS.
Before installing your card, you should read the technote contained in the /etc/readme/technotes/Net.epic file.
If you install more than one network card, you must specify a unique network ID (-l option) to every network driver.
If you install more than one epic-compatible PCI network card, you must also specify the -I option for every invocation of Net.epic. (Use -I0 for the first card, -I1 for the second, etc.)
Examples:
Start the Net.epic driver with default parameters:
Net.epic &
Start the Net.epic driver and force the speed to 100Mbit:
Net.epic -s100 &
Start two copies of the driver running on separate cards; one on logical network 1, the other on logical network 2:
Net.epic -I0 -l1 &
Net.epic -I1 -l2 &
Files:
Net.epic closes its standard input, standard output, and standard error immediately after initialization.
Error messages are displayed via the qnx_display_*() functions, not through standard error.
Signals:
The Net.epic driver ignores SIGPWR.
Exit status:
Net.epic terminates only upon encountering errors during initialization or upon getting a signal (i.e. being killed).
- 0
- Net.epic has shut down successfully and cleanly deregistered from Net.
- >0
- An error occurred during initialization.
See also:
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