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Connection Types
Figure 1
Female DB-9 Serial Connector
The female DB-9 connector is typically used as the "plug" that goes into a typical PC. If
you see one of these on the back of your computer, it is likely not to be used for serial
communication, but rather for things like early VGA or CGA monitors (not SVGA) or for
some special control/joystick equipment.
And this is a male "DB-9" connector (properly known as DE9M):
Figure 2
Male DB-9 Serial Connector
This is the connector that you are more likely to see for serial communications on a "generic"
PC. Often you will see two of them side by side (for COM1 and COM2). Special equipment
that you might communicate with would have either connector, or even one of the DB-25
connectors listed below.
2.3.2 RS-232C: DB-25
This is a female DB-25 connector (also known as DB25F):
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