Sun Microsystems Netra T4 AC100, Руководство по обслуживанию и системе

Страница: 180 / 284

10-26 Netra T4 AC100/DC100 Service and System Reference Manual • August 2001
FIGURE 10-13
USB and Parallel Port Functional Block Diagram
10.2.11 Parallel Port
The parallel port is managed by the SuperI/O component.
The parallel port is supported by an IEEE 1284-compliant parallel port controller
located on the SuperI/O ASIC. The parallel port controller is a PC industry-standard
controller that achieves a 2-Mbits/sec. (Mbps) data transfer rate. The parallel port
controller interface supports the ECP protocol as well as the following:
■
Centronics—Provides a widely accepted parallel port interface.
■
Compatibility—Provides an asynchronous, byte-wide forward (host to
peripheral) channel with data and status lines used according to their original
definitions.
■
Nibble mode—Provides an asynchronous, reverse (peripheral-to-host) channel,
under control of the host. Data bytes are transmitted as two sequential, four-bit
nibbles using four peripheral-to-host status lines.
EMI
filter
1
2
Parallel port
DB-25
Parallel
port
PCIO-2
ASIC
SuperI/O
USB ports
USB Peripherals
Serial
Port