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Cisco 12016, Cisco 12416, and Cisco 12816 Router Installation and Configuration Guide
OL-11495-01
Chapter 2 Preparing for Installation
GRP Port Connection Guidelines
Caution To maintain Class B EMI compliance, you must use shielded cables when
connecting to the auxiliary and console ports of original GRPs (part numbers
GRP= and GRP-B=). An updated version of the GRP-B= board (Rev. F0) does not
require shielded cables for Class B compliance.
GRP Auxiliary Port Signals
The GRP auxiliary port is a DB-25 DTE port for connecting a modem or other
DCE device to the router. The auxiliary port supports hardware flow control and
modem control.
Table 2-2 lists the signals used on the auxiliary port.
Tab l e 2-2 GRP Auxiliary Port Signals
Pin Signal Direction Description
1GND —Shield ground
2TxD Output Transmit data (to DCE)
3RxD Input Receive data (from DCE)
4RTS Output Request to send
(used for hardware flow control)
5CTS Input Clear to send (used for hardware flow control)
6DSR Input Data set ready
7GND —Signal ground
8DCD Input Carrier detect (used for modem control)
20 DTR Output Data terminal ready (used for modem control
only)
22 RING Input Ring