Black Box ME657A-M/F, ME658A-M/F Quick Start Manual

BERT LOOP

511/E RDL

NORMAL

511 LAL

1 2 3 4 5 6 7 8 1 2 3 4 5 6 7 8

OFFOFF

SW1 SW2

ME657A-M/F

SPECIFICATIONS:

Interfaces: Serial--EIA RS-232/ITU-TSS (CCITT) V.24;

Line--Two- or four-wire telco

Protocol: Synchronous or Asynchronous

BLACK BOX

Multi-Function

Line Driver

ME657A

XMT

INTRODUCTION:

The Multi-Function Line Driver (MFLD) is a carrier-controlled short-range modem that requires no AC power or batteries. The
MFLD operates across two wires (half-duplex) or four wires (full- or half-duplex), communicating with DTE's synchronously or
asynchronously, up to a maximum range of 12 miles (19.3 km). You can set the MFLD to any of twelve data rates form 1.2 K to

38.4 Kbps.
Multi-Function Line Drivers always communicate with each other synchronously. When connected to an asynchronous RS-232
device, an MFLD performs synchornous/asynchronous conversion.
The Multi-Function Line Driver has several features that enhance its overall performance, including automatic equalization,
transformer isolation, and Silicon Avalanche Diode surge protection. The MFLD also has strong diagnostics: It features V.52­compliant bit-error-rate (BERT) pattern tests and two V.54 test modes.
The Multi-Function Line Driver is housed in an ABS plastic case and comes with either a male or female DB25 connector and a
terminal block with strain relief.

RCVG

Clock Source: Internal, External (from DTE), or Received (from other Card) (user-selectable).
Data Format: Word length (including start bit, data bits, stop bits, and parity bit) must equal 8, 9, 10 or 11 bits

(user-selectable).

Flow Control: Transparent to all types of software (X-ON/X-OFF, robust X-ON/X-OFF, etc.) flow control; can be set

to support hardware flow control.
Operating Mode: Two-wire half-duplex or dour-wire full- or half-duplex (user-selectable).
Data Rate: 1,200 to 38,400 bps.
Isolation: 1500 volts RMS minimum using custom transformers.
Surge Protection: Silicon Avalanche Diodes.
Maximum Surge Protection: 600 watts dissipated after 1 msec.
User Controls: (2) Top-mounted toggle switches: LOOP (Remote digital or Local Analog Loopback), BERT (511 or

511/E V.52 diagnostics:

(2) Bottom-mounted 8-position DIP switches: (1) for data rate, clock source, protocol, and carrier control;

(1) for 2- or 4-wire operation, diagnostics, RTS/CTS delay, signaling-rate range, and word length.
Indicators: (2) Top-mounted LED's: Test (next to LOOP Switch), and ERROR (next to BERT Switch).
Diagnostics: ITU-TSS V.54 remote digital and local analog loopbacks; ITU-TSS V.52 BERT testing.
Connectors: (1) DB25 male/female (depending on model chosen); (1) 5 screw terminal block.
Power: From EIA RS-232 interface; Consumption: 56 to 70 mw

CONFIGURATION:

The Multi-Function Line Driver has two 8-position DIP switches-- SW1 and SW2--mounted on its underside. These configuration
switches allow you to select data rates, clocking methods, V.52 and V.54 test, word lengths, extended signaling rates, sync or
async protocol, and 2- or 4-wire operation.

SW1 (Positions 1 through 4): Set positions 1 through 4 of switch S1 to determine the data rate (valid for

both synchronous and asynchronous protocols) of the Line Driver.
SW1-1 SW-1-2 SW1-3 SW1-4 DATA RATE:
ON ON ON ON 1200 bps
OFF ON ON ON 1800 bps
ON OFF ON ON 2400 bps
OFF OFF ON ON 3600 bps
ON ON OFF ON 4800 bps
OFF ON OFF ON 7200 bps
ON OFF OFF ON 9600 bps
OFF OFF OFF ON 14,400 bps
ON ON ON OFF 19,200 bps
OFF ON ON OFF 28,800 bps
ON ON OFF OFF 38,400 bps

SW1 (Positions 5 and 6): Determines which transmit-clock source the Multi-Function Line Driver uses.

SW1-5 SW-6 Clock Source:
ON ON Internal Transmit Clock (default)
OFF ON Receive-Recover Clock
ON OFF External Transmit Clock

SW1-7: Determines whether the Multi-Function Line Driver operates synchronously or asynchronously.

SW1-7 Protocol:
ON Asynchronous (default)
OFF Synchronous

SW1-8: Determines whether the carrier is "constantly ON" or "controlled by RTS". In the "controlled by

RTS" setting, the Switch can support switched-carrier, multipoint, or hardware flow-control
applications.
SW1-8 Carrier:
OFF Constantly ON (default)
ON Controlled by RTS

SW2-1 and 2: Determines the word length that the Line Driver will expect for asynchronous or

synchronous data. For example, if you are using the most common data format
(1 start bit, 8 data bits, 1 stop bit, and no parity), you would use the factory-default
word-length setting (10 bits).
SW2-1 SW2-2 Word Length:
ON OFF 8 bits
ON ON 9 bits
OFF OFF 10 bits (default)
OFF ON 11 bits

SW2-3: Determines the degree of asynchronous data-rate fluctuation that the Line Driver will

accept (that is, how much variance from a given frequency level the MFLD will
tolerate).
SW2-3 Signaling-Rate Range:
OFF -2.5% to +1% (default)
ON -2.5% to +2.3%

SW2-4 and 5: Determines the amount of time the Line Driver waits after it "sees" RTS before it

sends CTS.
SW2-4 SW2-5 RTS/CTS Delay:
ON ON 7ms (default)
ON OFF 53 ms
OFF ON No Delay
OFF OFF No Delay

SW2-6 and 7: Determines whether the Line Driver operates in 2-wire or 4-wire mode. (For 2-

wire mode to work, SW1 position 8 must be ON.) In 4-wire mode, set position 7 to
switch SW2 to determine whether the MFLD operates in full duplex or half-duplex.
SW2-6 SW2-7 Operation:
ON ON 4-wire half-duplex
ON OFF 4-wire full-duplex
OFF ON 2-wire (Half-Duplex ONLY)

SW2-8: V.52 and V.54 Diagnostic Testing: To reset the V.54 circuit, turn switch S2 position 3

ON, then back OFF.
SW2-8 Test Mode:
OFF Tests Enabled (default)
ON Tests Disabled

INSTALLATION:

Once the Line Driver is properly configured, you can connect it to your system. The Line Driver supports data-only communication between two RS-232 devices at distances to 12 miles (19.3 km) and data rates to 38.4 Kbps. There are two essential requirements
for installing the Line Driver.

Open the unit by gently inserting a screwdriver into the special pry slot on the plastic case. Don't worry about breaking the plastic, but make sure you don't insert the screwdriver more than 1/4" into the enclosure, because you might damage the circuitry inside the
unit. Once the unit is open, you will be able to see the terminal blocks at the rear of the Line Driver's circuit board.

1. They work in pairs; you must have one at each end of the twisted-pair cable.

2. The Line Driver operates half-duplex over two wires (one twisted pair) or full- or half-duplex over four wires (two twisted pairs). In all applications, the twisted-pair wire must be between 19 and 26 AWG (higher gauges might limit the distance that can
be run), unconditioned, dry, and metallic. Both shielded and unshielded cable yield favorable results.

NOTE:
The Multi-Function Line Driver can only communicate in a closed data circuit with another Multi-Function Line Driver.
It will not work with dial-up analog circuits, such as those used with standard modems.

Modem-to-Modem Cabling using the terminal block: