|C H A P T E R 1|
The qfe Device Driver
This chapter gives a hardware overview of the SUNW,qfe device, provides information on the operating speeds and modes for the SUNW,qfe device, and discusses auto-negotiation. The following sections describe features of the SUNW,qfe device.
The SUNW,qfe device provides 10BASE-T or 100BASE-T networking interfaces using the Fast Ethernet Parallel Port SCSI (FEPS) ASIC and an internal transceiver. The driver automatically sets the link speed to 10 or 100 Mbps and conforms to the 100BASE-T IEEE 802.3u Ethernet standard .
The FEPS (SBus based) ASIC provides the SBus interface and Media Access Control (MAC) functions. The PFEX (PCI-bus based) ASIC provides the PCI interface and Media Access Control (MAC) functions. The internal transceiver, which connects to an RJ-45 connector on all of the above hardware devices, provides the physical layer functions.
The auto-negotiation protocol , as specified by the 100BASE-T IEEE 802.3u Ethernet Standard , selects the operation mode (half-duplex or full-duplex) at boot time or when the link state changes (the link fails or tries to connect). The auto-negotiation protocol also selects the speed and the full-duplex or half-duplex mode.
Details of the way the SUNW,qfe device uses auto-negotiation are provided in Appendix A .
Identifies all link partner-supported modes of operation
Advertises its capabilities to the link partner
Selects the highest common denominator mode of operation based on the following priorities (in decreasing order):
If adapters or systems are connected to a link partner and the auto-negotiation protocol fails to operate successfully, you can configure the device so it does not use this protocol. This forces the driver to set up the link in the mode and speed of your choice.