Meinberg TCR510PCI, Operating Instructions Manual

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The 9 pin D-Sub-connector is wired to the board’s serial port. Pin assignment can
be seen from the figure above. This port can not be used as serial port for the
computer. Instead, the clock uses the port to send out Meinberg's standard time string
in order to control an external display or some other external device. The string is
sent out once per second, once per minute or if requested by an incoming ASCII ‘?’.
It is also possible to change the board’s board time by sending such a string towards
the clock. Transmission speed, framing and mode of operation can be modified using
the monitor software. The string format is described in the section ‘Technical
Specifications’ at the end of this manual.
Pin assignments of the D-Sub-connector
Only the signals of the serial interface are connected to the D-Sub-plug directly. If
another signal shall be connected to a pin of the plug, a DIP-switch must be set to the
‘ON’ position.
Whenever an additional signal is connected to the rear panel,
special care must be taken to the configuration of the cable used
with the connector. If pins with TTL level and RS-232 levels are
connected to each other, the circuits on the board may be dama-
ged.
Only one of the switches 5
or
4 may be put in the ‘ON’ position to connect the
pulse per second with TTL level or with RS-232 level to pin 8 of the plug. The table
below shows the pin assignments for the connector and the DIP-switch assigned to
each of the signals:
Pin Signal SWITCH
1 + 5V 3
2 RxD in (RS-232) -
3 TxD out (RS-232) -
4 PPM out (TTL) 6
5 GND -
6 + PWM in 1
7 - PWM in 2
8 PPS out (TTL/RS232) 5/4
9 (reserved) 8
Those signals which do not have DIP-switch assigned are always available at the
connector. All DIP-switches not assigned are reserved and should remain in the ‘OFF’
position.