Black Box ME760A-R2, Руководство пользователя

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20
LDM-MR19.2
Table 3-1. DB25 Pinout and Interface-Signal List (continued)
CCITT EIA DTE SIGNAL
V.24 RS-232-C PIN NAME DESCRIPTION
109 CF 8 Receive Line The LDM-MR19.2 always sends a “high”
Signal Detector (positive) level to the local DTE except when
(Carrier Detect) the LDM-MR19.2 detects carrier loss or is in
local or remote digital loopback.
113 DA 24 External Trans. Synchronous data-rate-clock input received
Signal Element from the local DTE. Governs the Transmitted
Timing Data signal. See the Note below.
114 DB 15 Transmitter Synchronous data-rate-clock output sent to
Signal Element the local DTE. Governs the Transmitted Data
Timing signal. See the Note below.
115 DD 17 Receiver Signal Synchronous data-rate-clock output sent to
Element Timing the local DTE. Governs the Received Data
signal. See the Note below.
142 25 Test Indicator The LDM-MR19.2 sends a “high” (positive)
level to the local DTE during any test mode.
141 18 Loop 3 When it receives this control signal from the
Test Command local DTE, the LDM-MR19.2 goes into Local
Analog Loopback.
140 21 Loop 2 When it receives this control signal from the
Test Command local DTE, the LDM-MR19.2 forces the
remote modem into Remote Digital Loopback.
NOTE:
When the LDM-MR19.2 is operating synchronously, transitions of the Transmitted Data and
Received Data signals happen at the same time as positive-going (“rising edge”) transitions of the active
clock signal.