Meinberg TCR510PCI, Руководство по эксплуатации

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Features TCR510PCI
The board TCR510PCI was developed for computer systems with PCI-bus. It is
designed as an universal board and can be used in systems with either 3.3 V or 5 V PCI
slots therefore. The module supports clock speeds of 33 MHz and 66 MHz. TCR510PCI
serves to receive and decode modulated (AM) and unmodulated (DC Level Shift) IRIG
and AFNOR time codes. AM-codes are transmitted by modulating the amplitude of a
sine wave carrier, unmodulated codes by variation of the width of pulses.
Automatic gain control within the receive circuit for unmodulated codes allows
decoding of IRIG signals with a carrier amplitude of 600 mVpp to 8 Vpp. The input
stage is elecctically insulated and has an impedance of 50
Ω
, it is accessible via the BNC-
connector in the bracket of TCR510PCI.
Unmodulated time codes must be connected to the D-Sub-plug of the module. An
onboard photocoupler insulates the internal receive circuit. In delivery state of
TCR510PCI the contacts of the D-Sub-plug are not connected to the photocoupler. Two
DIP-switches must be set to the ‘ON’ position for making this connection.
The board TCR510PCI provides a configurable serial interface (RS-232), a pulse per
second (PPS) with TTL or RS-232 level and a pulse per minute (PPM) with TTL level.
Like the photocoupler, these signals are only connected to the D-Sub-plug after setting
DIP-switches into the ‘ON’ position.
Software running on the computer can read out information regarding date, time and
status of the IRIG receiver. Access to the board is made via writing to/reading from I/O
ports. It is possible but not necessary to let the board generate periodic hardware
interrupts on the computer bus.
Driver software supplied with the board is keeping the computer’s system time
synchronous to the board time. If the diskette delivered with TCR510PCI doesn’t
include a driver for the used operating system, it can be downloaded free of charge at:
http://www.meinberg.de/german/sw/
Manuals for the drivers are available at this site also.
The microprocessor system of TCR510PCI is equiped with a Bootstrap-Loader and a
Flash-EPROM. These features enable updating of the onboard software via the serial
RS-232 interface COM0 by using the Meinberg program ‘Flash509’.