Datasheet

Identifying Characteristics of Ports and Cables
55
Peripheral Port Connector Types
Computer ports are interfaces that allow other devices to be connected to a computer. Their
appearance varies widely, depending on their function. In this section we’ll examine the fol-
lowing types of peripheral ports:
D-subminiature
ßN
RJ-series
ßN
Other types
ßN
D-subminiature Connectors
D-sub connectors, for a number of years the most common style of connector found on
computers, are typically designated with DXn, where the letter X is replaced by the let-
ters A through E, which refer to the size of the connector, and the letter n is replaced by
the number of pins or sockets in the connector. D-sub connectors are usually shaped like a
trapezoid, as you can see in Figure 1.36. The nice part about these connectors is that only
one orientation is possible. If you try to connect them upside down or try to connect a male
connector to another male connector, they just won’t go together, and the connection can’t
be made. Table 1.3 lists common D-sub ports and connectors as well as their most common
uses. Be on the lookout for the casual use of “DB” to represent any D-sub connector. This
is very common and is accepted as an unwritten de facto standard.
At the bottom left in Figure 1.36 is a DE15F 15-pin video port, in the center is a DB25F
25-pin female printer port, and on the right is a DE9M 9-pin male serial port.
TABLE 1.3 Common D-sub Connectors
Connector Gender Use
DE9 Male Serial port
DE9 Female Connector on a serial cable
DB25 Male Serial port or connector on a parallel cable
DB25 Female Parallel port, or connector on a serial cable
DA15 Female Game port or MIDI port
DA15 Male Connector on a game peripheral cable or MIDI cable
DE15 Female Video port (has three rows of 5 pins as opposed to
two rows)
DE15 Male Connector on a monitor cable
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