Ultra electronics VersaMux-4000, Руководство по эксплуатации и установке

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Planning the Timing Chapter 4: Getting Started
Page 4-18 VersaMux-4000 Operation & Installation Guide Part No. 24001157
Revision C
Port Timing
The VersaMux-4000 can also accept timing from one of its (non-aggregate) ports.
This section describes using Port Timing on the VersaMux-4000.
Port Timing, VersaMux = DTE
Figure 4-22 shows the DTE mode VersaMux-4000 recovering its master clock from
one of its ports. With the TxClkSrc parameter set to TxClkIn , the VersaMux uses
the Tx Clock signal from the DCE (Transmit Signal Element Timing- DCE Source) to
clock the Transmitted Data out to the DCE. It also returns this signal to the DCE as
the DTE Tx Clock (Transmit Signal Element Timing- DTE Source). Note that the
VersaMux uses the DCE Rx Clock (Receiver Signal Element Timing- DCE Source) to
clock in the Received Data from the DCE. Typically the DCE would use the same
source as the VersaMux Port to generate its system reference.
Figure 4-22
VersaMux-4000, DTE Mode, Port Timing, TxClkSrc = TxClkIn
Figure 4-23 is similar to Figure 4-22 except that with the TxClkSrc parameter set
to System , the VersaMux uses its system reference to clock the Transmitted Data
out to the DCE and sends this signal to the DCE as the DTE Tx Clock (Transmit
Signal Element Timing- DTE Source). Note that the VersaMux uses the DCE Rx
Clock (Receiver Signal Element Timing- DCE Source) to clock in the Received Data
from the DCE. Typically the DCE would use the VersaMux Tx Clock (DTE) to
generate its system reference.
Figure 4-23
VersaMux-4000, DTE Mode, Port Timing, TxClkSrc = System
DCE Device
(IE: Satellite
Modem)
ClkRef
NRZ Interface
Transmitted Data
Tx Clock (DCE)
Tx Clock (DTE)
Rx Clock (DCE)
Rx Data
Primary
Reference Source
(PRS)
VersaMux-4000 (DTE)
Mode = DTE
ClkRef = Port (Port-1, Port-2, Port-3, Port-4)
TxClkSrc = TxClkIn
Port Interfaces
DCE Device
(IE: Satellite
Modem)
ClkRef
NRZ Interface
Transmitted Data
Tx Clock (DCE)
Tx Clock (DTE)
Rx Clock (DCE)
Rx Data
VersaMux-4000 (DTE)
Mode = DTE
ClkRef = Port (Port-1, Port-2, Port-3, Port-4)
TxClkSrc = System
Port Interfaces
Primary
Reference Source
(PRS)