Sun Microsystems Netra T4 AC100, Руководство по обслуживанию и системе

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Chapter 10 Functional Description 10-15
Ethernet Leaf
The Ethernet interface supports two DMA channels for full duplex. the PCIO-2
Ethernet interfaces through PHY 6612 and COMBO magnetics and RJ45 connector.
See Section 10.2.13, “Ethernet” on page 10-31 for details.
USB Leaf
USB (Universal Serial Bus) is a standard defined for the PC industry that provides
connectivity to low-cost low-bandwidth peripherals.
USB defines a tree topology through hub devices although logically it behaves as a
bus. The USB standard defines two data transfer rates: 1.5 and 12 Mbit/sec. USB
supports live connect and disconnect of devices (hot plugging).
The PCIO-2 USB channel engine has a single DMA engine with 1 Kbit of internal
buffering. It serves as the USB host controller and a hub with four ports. As a host
controller it manages control flow, data flow and connections. The PCIO-2 USB host
controller programming model is Open HCI compatible.
10.2.3.3 EBus Leaf
EBus is a byte-wide I/O bus that provides the ability to interface to instruction set
architecture devices. In a Netra T4 system there are four devices on this bus (the
audio module is not used):
■
Boot PROM (Flash memory)
■
OpenBoot PROM (OBP) prompt
■
Power On Self Test (POST)
■
OpenBoot Diagnostics (OBDiag)
■
Synchronous serial controller (RS-232/RS-423 ports)
■
SuperI/O chip
■
Parallel port
■
TOD clock (socketed 3 V lithium battery)
■
I2C controller
The TOD clock function is implemented by the real time clock inside the SuperI/O
ASIC. The nonvolatile RAM is implemented by a I2C serial EEPROM and part of the
boot PROM.