Specifications

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CHAPTER 4: Installation
4.2.2 C ONNECTING THE MFLD TO A DCE D EVICE
Because the Multi-Function Line Driver is wired as a DCE device, you can’t
plug it directly into another DCE (modem, multiplexor, etc.) device. If you
must make such a connection, use a null-modem cable pinned according to
Table 4-3 below. Because the MFLD is interface-powered, this cable should
be as short as possible (we recommend 6 ft. [1.8 m] or less).
NOTE
When you connect the Multi-Function Line Driver to another DCE device,
you should configure the MFLD for the “external” clock source (see the
entry for SW1 Positions 5 and 6 in Section 3.2).
Table 4-3. Pinout for a Null-Modem Cable
Conecting the MFLD to Another DCE
MFLD End: DCE End:
DB25 Male DB25 Male
Pin No. Pin No.
1-------------------------------------------------1
2-------------------------------------------------3
3-------------------------------------------------2
4-------------------------------------------------8
6------------------------------------------------20
7-------------------------------------------------7
8-------------------------------------------------4
17-----------------------------------------------24
20------------------------------------------------6
24-----------------------------------------------17