IBM PC 100, Техническое руководство

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Chapter 2. Connectors and Jumpers
Parallel-Port Modes
The parallel port can operate in five different modes. One is a standard, unidirectional mode; the other
four are extended, bidirectional modes that provide additional function and higher performance. Refer to
the documentation that comes with your printer or other parallel device to determine the appropriate
parallel mode to use and to get information on the required device drivers.
Standard This
AT-compatible mode is the default mode. In this mode, the parallel port is
limited to writing information to the device attached to it. This mode can be used
with most IBM-compatible parallel printers.
Bidirectional This
PS/2-compatible mode is a bidirectional mode used for data transfer to other
PC systems and supported devices.
ECP The
extended capabilities port (ECP) mode is a high-performance, bidirectional
mode that uses direct memory access (DMA) for data transfer to a high-speed
printer or to other devices.
EPP The
enhanced parallel port (EPP) mode is a high-performance, bidirectional mode
that has capabilities similar to the ECP mode. The main difference between the two
modes is that EPP data transfers are processor-initiated instead of DMA-initiated.
EPP supports the connection of up to eight external devices such as hard disk
drives, CD-ROM drives, tape drives, diskette drives, and a printer to the parallel
port. These devices can be connected to each other in a
daisy-chain arrangement,
or they can be connected through an external multiplexor. The attachment of
multiple devices requires device drivers supplied by the device manufacturers.
ECP/EPP This mode combines the capabilities of the ECP and EPP modes. Select this mode
to connect both ECP and EPP devices to the parallel port.
To select the mode of operation for the parallel port, use the Configuration/Setup Utility program.
Monitor Connector
PC 100 and PC 300 computers have a 15-pin monitor connector. The following figure shows the signal
and pin assignments for the system board monitor connector.
Figure 25. Monitor Connector Signal and Pin Assignments
Pin Signal Pin Signal
1 Red (out) 2 Green (out)
3 Blue (out) 4 Not used
5 Ground 6 Red ground
7 Green ground 8 Blue ground
9 Not used 10 Ground
11 Not used 12 DDC2 serial data (I/O)
13 Horizontal sync (out) 14 Vertical sync (out)
15 DDC2 clock (I/O)
Chapter 2. Connectors and Jumpers
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