Manual browser: ep(4)

EP(4) Kernel Interfaces Manual EP(4)


epdriver for 3Com EtherLink III Ethernet interfaces


ep0 at isa? port ? irq ?
ep* at isapnp?
ep* at eisa? slot ?
ep* at mca? slot ?
ep* at pci? dev ? function ?
ep* at pcmcia? function ?


The ep device driver supports the 3Com EtherLink III family of Ethernet cards.

The 3c515 is an ISA 10/100 card with DMA capability. The chipset is similar to that of the 3c905, with some changes to make it work with the more limited ISA bus address space. This card is supported, although DMA is not used.

The EISA and PCI 3c59x devices use an older DMA engine which is not capable of multi-segment DMA. DMA on these devices is not used.

The 3c529 is a MCA device, and doesn't support DMA.

The PCI 3c90x devices have multi-segment DMA capability, which is not supported by the ep driver. To use the DMA capabilities of these cards, the ex(4) driver must be used.

The PCI 3c90xB devices are not supported by the ep driver, as they do not include support for programmed I/O. These devices are supported by the ex(4) driver.

The 3c575 is a CardBus device, and is supported by ex(4) driver.


There are 3 main chipset classes supported by the ep driver. Each has their own media selection capabilities.

The first class is the “3c509” class. This includes the 3c509, 3c509B, 3c529, 3c579, 3c562, and 3c589. These devices can support 10BASE-T, 10BASE2, and 10BASE5. Available media will be displayed when the device is found by the kernel.

The second class is the “Vortex” class. This includes the 3c592, 3c579, 3c590, and 3c595. This class also includes the 3c900-TPO and 3c900-COMBO; they use the “Boomerang” chipset, but use Vortex-style media selection. These devices have many different media types varying by model. Some models have an external MII connector for connecting an external PHY. This is supported by means of the “manual” media type. Available media will be displayed when the device is found by the kernel.

The third class is the “Boomerang” class. This includes the 3c515, 3c905, and 3c574. These devices support media selection via MII. The 3c515 and 3c905 have an nsphy(4), and the 3c574 has a tqphy(4), for this purpose. See ifmedia(4) and mii(4) for more information.


Supported cards include:
ISA 10Mbps card, in BNC and multiport variants
ISA Plug-and-Play 10Mbps card, in BNC and multiport variants
ISA Plug-and-Play 10/100 card with UTP
MCA 10Mbps card, in UTP+AUI and BNC+AUI variants
PCMCIA 56K modem-10/100Mbps Ethernet combo card with dongle
PCMCIA modem-10Mbps Ethernet combo card with dongle
PCMCIA 10/100Mbps card with dongle
EISA 10Mbps card, in UTP, BNC, and multiport variants
PCMCIA 10Mbps card with dongle
PCI 10Mbps multiport card with DMA capability
EISA 10Mbps card with DMA capability
PCI 10/100Mbps with different media options and DMA capability
EISA 10/100Mbps card with DMA capability
PCI 10Mbps card in 10BASE-T and multiport variants with DMA capability
PCI 10/100Mbps card in 10BASE-T, multiport, and fast variants with DMA capability


EtherLink III cards have no jumpers to set the address. 3Com supplies software to set the address of the card in software. To find the card on the ISA bus, the kernel performs a complex scan operation at IO address 0x100. Beware! Avoid placing other cards at that address!

The 3Com configuration utilities can `autosense' the active media and save it as default. The saved default medium is the medium that was active at the time the configuration utility was run. The ep driver does not yet re-autosense the active media at boot time. If the EEPROM autosense bit is set, the driver simply uses the media type sensed and saved when the configuration utility was run.


ep0: reset (status: %x)
The driver has encountered a FIFO underrun or overrun. The driver will reset the card and the packet will be lost. This is not fatal.
ep0: eeprom failed to come ready
The EEPROM failed to come ready. This probably means the card is wedged.
ep0: 3c509 in test mode. Erase pencil mark!
This means that someone has scribbled with pencil in the test area on the card. Erase the pencil mark and reboot. (This is not a joke.)
October 30, 2007 NetBSD 7.0