Specifications

Chapter 1. Introduction
12
The ETU01-Plus can select from one of five clocking mode settings.
Clock mode 0 (DCE 1):
The ETU01-Plus data channel operates as a DCE and provides both transmit and
receive clocks (recovered timing) to the data terminal equipment connected to the
user channel. The clocks are locked to the recovered E1 timing.
Figure 1.1 Recovery timing
Clock mode 1 (DCE 2):
The ETU01-Plus data channel operates as a DCE and provides both transmit and
receive clocks (internal oscillator timing) to the data terminal equipment connected to
the user channel. The clocks are locked to the oscillator timing.
Figure 1.2 Internal Timing
The internal oscillator provides the clocking source for both the user data receive
timing out the RC and TC pins and the E1 transmit timing.
DTE
Connected
Equipt.
DCE
Data
Port
E1
E1
transceiver
Clock Mode 0: Recovery
TC
RC
TX
RX
DTE
Connected
Equipt.
DCE
Data
Port
E1
E1
transceiver
Clock Mode 1: Internal
OSC
TC
RC
RX
TX