Chapter 1. Introduction
TSU Clock Sources
The TSU is operable from various clock sources permitting it to perform properly in many different applications. The network interface clocking options are set by using the Network (NI) Configuration menu options. There are three clock source options available.
•Network
•DTE Timed
•Internal Timing
The clocking option selected always designates the clock source for transmission. Clocking necessary for receiving data will always be recovered from incoming data.
Network Timed
The network is the source of timing. The received data clocking is looped back to the network where it is used to determine the transmission timing. This option is also referred to as looped timed as the transmission clock is derived from the received clock. See Figure
| OSC |
T1 XMIT |
|
( D S U ) | Network |
T1 Receive | Interface |
| |
| NX56K/64K |
| DTE CLOCK |
| DTE |
Figure 1-4. Network Timed Clock Source
TSU User Manual |
