Meinberg TCR511PEX - Manual (Page 14)

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Photocoupler input
Pulse width modulated (DC Level Shift) codes are insulated by an onboard photocoup-
ler. The connection scheme is shown below:
The internal series resistance allows direct connection of input signals with a maxi-
mum high level of +12 V (TTL or RS-422 for example). If signals with a higher
amplitude are used, an additional external series resistance must be applied for not
exceeding the limit of the forward current of the input diode (50 mA). The forward
current should not be limited to a value of less than 10 mA to ensure save switching
of the photocoupler.
Configuration of TCR511PEX
The selection of the IRIG code, configuration of the serial interface and a possible offset
of the received IRIG time to UTC must be set up by the monitor software via the PCI-
Express bus. In contrast to AFNOR NFS 87-500 the IRIG telegram containes only the
day of year (1...366) instead of a complete date. To ensure correct function of
TCR511PEX, the date stored in the realtime clock of the board must be
set when using IRIG codes therefore. This setting can be done by a
terminal software also.
If the time zone of the received IRIG code is not UTC, the local offset
to UTC must be configured to ensure correct function of the driver
software. If the local time zone is MEZ for example, the board must be set to a local
offset of ‘+60min’ (MEZ = UTC + 1 h).
The serial interface COM0 can be configured to send a time telegram with reference to
UTC or to the received local IRIG time.