Motorola MVME2600 manual Serial Port 4 Transmit Clock Receiver Buffer Control J20

MVME2603/2604 Base Board Preparation 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-compatibleversions 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.

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