Media5 Mediatrix 3308, Hardware Installation Manual

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Appendix B - Cabling Considerations Serial Console (RS-232)
38 Mediatrix 3300 – Analog Gateway
The RJ-11 pair of wires is wired so that pins 3 and 4 are connected to the Ring and Tip, which meets the
following requirements:

EIA/TIA-IS 968

CS-03 Issue 8, Part III requirements.
Serial Console (RS-232)
DTE or DCE
A device that communicates over a synchronous serial interface is either a DTE (Data Terminal Equipment)
or DCE (Data Communications Equipment) device. DTE devices usually connect to DCE devices. The
Mediatrix 3300 and a PC are a DTE, while a CLI terminal is a DCE.
Crossover Cable (Null Modem)
The crossover version of the DB-9 cable (also known as null modem) uses a female-to-female cable in any
application where you wish to connect the Mediatrix 3300 with another DTE device such as a PC or
workstation. This cable is required for CLI application.
The purpose of a null-modem cable is to permit two RS-232 “DTE” devices to communicate with each other
without modems or other communication devices (i.e., DCEs) between them.
To achieve this, the most obvious connection is that the TD signal of one device must be connected to the RD
input of the other device (and vice versa).
Figure 17: DB-9 Crossover Connectivity
5 Not used
6 Not used
Table 18: RJ-11 Pinout Information (Continued)
Pin # Function
Warning:
The RJ-11 cable should comply with UL 1863 and CSA C22.2 No 233 standards.
2- RX
3- TX
5- GND
TX -2
TX -3
GND -5
7- SG
8- CD
SG -7
CD -8
6- DSR
1- DCD
4- DTR
DSR -6
DCD -1
DTR -4
4- DTR DTR -4