MVME2603/2604 Base Board Preparation
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1
Serial Port 4 Transmit Clock Receiver Buffer Control (J20)
As described in other sections, a complete configuration of Serial Port 4
requires that you set the following jumper headers on the
MVME2603/2604 or the transition module:
❏
J16 (Serial Port 4 receive clock configuration) on MVME712M-
compatible versions of the base board
❏
J17 (Serial Port 4 transmit clock configuration)
❏
J20 (Serial Port 4 transmit clock receiver buffer control) on
MVME712M-compatible versions of the base board
❏
J15 on the MVME712M transition module or J3 on the MVME761
(Serial Port 4 clock configuration)
A transmit clock receiver buffer (controlled by header J20) is associated
with Serial Port 4. Installing a jumper on J20 enables the buffer. Removing
the jumper disables the buffer. The factory configuration has the Serial
Port 4 buffer enabled.
J20 remains open on MVME761-compatible versions. On MVME712M-
compatible versions, J20 is set in tandem with J17 to configure the Serial
Port 4 transmit clock. If one deviates from the factory configuration, so
must the other.
Figure 1-9
and
Figure 1-10
(for the MVME712M) and
Figure 1-14
and
Figure 1-15
(for the MVME761) diagram the overall jumper settings
required on the MVME2603/2604 and transition module for a Serial Port
4 DCE or DTE configuration.
