Black Box ME444A-R3, ME444AE-R3, ME445C-X.21, ME445C-35, ME445C-530, ME444AE-530-R3 manual Operation

CHAPTER 5: Operation

2

4

6

E

B

D

PWR

RTS

TD

RD

DCD

TEST ERR

RPF

DIG

ANA

REM

PATT

1

3

5

7

A

C

Figure 5-2. The front panel of the rackmount card line driver.

Table 5-1. The controls.

The Item labels in this table correspond to those in Figures 5-1 and 5-2.

ITEM	CONTROL	FUNCTION
A	DIG	Pressing the local digital loopback button causes the local LDM-MR256 to
		loop received data and clock to its transmitter. Data Set Ready goes low.
B	ANA	Pressing the local analog loopback (V.54 Loop 3) button causes the local
		LDM-MR256 to loop its transmitter output back to its receiver. This
		loopback may also be activated from the DTE when the “ALB DTE” jumper
		is set to EN.
C	REM	Pressing the remote digital loopback (V.54 Loop 2) switch causes the
		remote LDM-MR256 to loop received data and clock to its transmitter.
		Data Set Ready goes low. This loopback may be also activated from the
		DTE when the “RLB DTE” strap is set to EN.
D	PATT	Pressing the PATT button causes the LDM-MR256 to send and receive a
		511 test pattern. If errors are encountered, the ERR LED becomes
		steadily lit or blinks. Receive Data and Clear to Send go low. Note: The
		unit’s “CARRIER” jumper should be set to ON; if it is set to CNTRL, the
		RTS signal must be high.
E	RPF	Remote Power Failure resets the ERR/RPF LED.

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