Technical Information Operating Instructions DCF77 PCI511
Impressum Meinberg Funkuhren GmbH & Co. KG Auf der Landwehr 22 D-31812 Bad Pyrmont Phone: Fax: ++49 52 81 - 9309-0 ++49 52 81 - 9309-30 Internet: http://www.meinberg.de Email: info@meinberg.
Table of Contents Impressum............................................................................................ 2 Driver diskette ..................................................................................... 5 Readme file .......................................................................................... 7 General information about DCF77 ...................................................... 9 Overview ..................................................................................
Driver diskette 5
Readme file The driver diskette contains a file called „readme.txt“, which helps installing the driver correctly. The content of this file is as follows: Installation Instructions ------------------------Execute Setup.exe and choose the installation directory. By default, the installation directory is: C:\Program Files\Meinberg\MbgMon Then shut down the computer, install the Meinberg radio clock plug-in board into a free slot and reboot. Now you are asked to install a driver. The driver file MEINBERG.
General information about DCF77 The radio clocks made by Meinberg receive the signal from the long wave transmitter DCF77. This long wave transmitter installed in Mainflingen near Frankfurt/ Germany transmits the reference time of the Federal Republic of Germany. This time reference is either the Central European Time (Mitteleuropäische Zeit, MEZ) or the Central European Summer Time (Mitteleuropäische Sommerzeit, MESZ).
Overview Because the radio clock PCI511 is designed as an universal board for computers with PCI bus, operation within 3.3V and 5V systems is possible. 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.
Block diagram PCI511 11
Connectors and LEDs in the rear panel The rear panel includes the antenna connector, three status LEDs, the BSL button, and a 9 pin sub D connector (see figure below). antenna free run field strength modulation BSL key RxD TxD GND The LEDs let the user check for proper receiver operation. The upper, red LED is on if the clock is not synchronous to DCF77. This LED can only change when the minute changes (seconds increment from 59 to 0).
Pin assignments of the 9 pin connector When the clock is being shipped, only the signals needed for the serial port are gated to their pins at the 9 pin connector. If another signal shall be available outside the computer, the corresponding lever of the DIL switch on the board must be set to the ON position to connect that signal to its associated pin. Whenever an additional signal is connected through to the rear panel, special care must be taken to the configuration of the cable used with the connector.
Aligning the antenna Generally, the exact alignment of the antenna is important. It has to be placed in longitudinal direction to the transmitter (Frankfurt), see arrow printed on the label of the antenna. A distance of several meters to TV- or computer monitors, to computers or microprocessor boards should be kept. These devices can produce interference fields that lead to a poor or no DCF77 receiption.
Modulation is displayed as a LED, the DCF77 field strength as a bar graph. Optionally, the modulation signal can be made audible via the speaker of the computer.
Technical specifications RECEIVER: Direct conversion quadrature receiver with automatic gain control Bandwidth: approx.
CONFIGURABLE TIME ZONES: Central European Time CET/CEST (default), always CET (no daylight saving time), UTC, East European Time EET/EEST (CET/CEST + 1h) SERIAL INTERFACE: PULSEOUTPUTS: Transmission Speed: Framing: Mode of Operation: 300 through 9600 Baud 8N1, 7E2, 8N2, or 8E1 send string per second, per minute, after request ´?´ received Output String: Meinberg standard time string (described below) Pulses every second (PPS) with TTL- and RS232-level, pulse duration 100 msec, active high Pulses every
Firmware updates Whenever the on-board software must be upgraded or modified, the new firmware can be downloaded to the internal flash memory via the radio clock's serial port COM0. There is no need to open the computer case and insert a new EPROM. If the button behind a hole in the rear slot cover is pressed twice, a bootstrap loader is activated and waits for instructions from the serial port COM0.
Declaration of Conformity Hersteller Manufacturer Meinberg Funkuhren GmbH & Co.
Format of the Meinberg Standard time string The Meinberg Standard time string is a sequence of 32 ASCII characters starting with the STX (start-of-text) character and ending with the ETX (end-of-text) character. The format is: D:dd.mm.yy;T:w;U:hh.mm.ss;uvxy The letters printed in italics are replaced by ASCII numbers whereas the other characters are part of the time string. The groups of characters as defined below: Start-Of-Text (ASCII code 02h) dd.mm.
PCI511 component layout 21
