Meinberg DCF77 PCI32, Operating Instructions Manual

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6
Overview
The radio clock PCI32 is designed to operate in computers with PCI bus. An external
ferrit antenna makes the signal from DCF77 available to the on-board long wave
receiver. The demodulated time marks are decoded by the clock´s microprocessor. If
no errors are detected in the current time message an additional plausibility check
against the previous time message is performed. If that plausibility check passes, too,
the buffered real time clock on the board is synchronized corresponding to the
decoded time and date.
Software running on the computer can read out the date/time/status and some more
information. 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.
Utility programs supplied with the boards include PCPSDRV.COM, a resident
driver (TSR) for DOS/Windows that keeps the computer´s system time synchronous
to the board time and PCPSINFO.EXE, a status display which simplifies installation.
Drivers for OS/2, Windows NT, or NetWare can be ordered separately.
Pulse Outputs
The radio clock PCI32 generates pulses whenever a new second (P_SEC) or a new
minute (P_MIN) begins. The P_SEC pulse is available with TTL level (0/+5V) and
RS-232 level (-3..12V/+3..12V), the P_MIN signal with TTL level only. If required,
DIL switches can be set up to direct each of the pulses to a corresponding pin of the 9
pin connector in the rear panel.