Memotec CX900e, Hardware Reference Manual, Page: 81 / 200

7 UNIVERSAL I/O CARD
3006M100-002
7-7
7.3.3 Clock Source Configuration
Each port is configurable for TXC or ETXC mode. TXC mode means that only
the standard transmit clock TXC is available for the transmit data, i.e., the clock is
output from the DCE and input to the DTE. ETXC mode means that only the
standard external (or DTE) transmit clock (ETXC) is available for the transmit
data (from DTE to DCE). Clock source configuration connectors are located at
J15, J25, J35, J45 and J55.
Split Clocking
The TXC/EXTXC selector is used to support split clocking on the Universal I/O.
An external adapter (part # CBLA0031-000) is required to perform split clocking.
Table 7-2 summarizes the appropriate configuration required:
Figure 7-6 demonstrates the PCB orientation for TXC configuration.
7.4 Power Requirements
Power
Consumption
1.63 Watts (3.3V
5.4 Watts (5V)
Power Source
The motherboard 120-pin connector su12 VDC to the card and provides
the Ground return. An on-board switching regulator pr5 VDC and +3.3
VDC to the card circuits.
Table 7-2 TXC/EXTXC Settings
Protocol Mode TXC/EXTXC Adapter
V.24/V.35 (DCE/DTE) non-split clock TXC not required
V.24/V.35 (DCE/DTE) split clock EXTXC CBLA0031-000
X.21 (DCE/DTE) split clock/non-split clock EXTXC not required
Figure 7-6 TXC Configuration
T XC
ET XC