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Format of the NMEA (RMC) string

The NMEA String is a sequence of 65 ASCII characters starting with the ‘$’
character and ending with the characters CR (carriage return) and LF (line-feed). The
format is:

$GPRMC,hhmmss.ss,A,bbbb.bb,n,lllll.ll,e,0.0,0.0,ddmmyy,0.0,a*hh<CR><LF>

The letters printed in italics are replaced by ASCII numbers or letters whereas the
other characters are part of the time string. The groups of characters as defined
below:

$

start character (ASCII-Code 24h)

hhmmss.ss

the current time:
hh

hours

(00..23)

mm minutes

(00..59)

ss

seconds

(00..59, or 60 while leap second)

ss

fractions of seconds (1/10 ; 1/100)

A

Status

(A = time data valid)
(V = time data not valid)

bbbb.bb

latitude of receiver position in degrees
leading signs are replaced by a space character (20h)

n

latitude, the following characters are possible:
‘N’ north of equator
‘S’ south d. equator

lllll.ll

longitude of receiver position in degrees
leading signs are replaced by a space character (20h)

e

longitude, the following characters are possible:
‘E’ east of Greenwich
‘W’ west of Greenwich

ddmmyy

the current date:
dd

day of month

(01..31)

mm month

(01..12)

yy

year of the century (00..99)

a

magnetic variation

hh

checksum (EXOR over all characters except ‘$’ and ‘*’)

<CR>

carriage-return; ASCII-Code 0Dh

<LF>

line-feed; ASCII-Code 0Ah

Summary of Contents for GPS163TDHS

Page 1: ...FUNKUHREN GPS163TDHS Technical Information Operating Instructions Incl Windows Software GPSMON32...

Page 2: ...Impressum Werner Meinberg Auf der Landwehr 22 D 31812 Bad Pyrmont Telefon 49 0 52 81 9309 0 Telefax 49 0 52 81 9309 30 Internet http www meinberg de Email info meinberg de October 28 2004...

Page 3: ...ble time codes 11 Code generation 11 IRIG standard format 12 AFNOR time code format 13 Assignment of CF Segment in IEEE1344 mode 14 Installation 15 Power supply 15 Mounting the antenna 15 Powering up...

Page 4: ...fications of antenna 23 Assembly with CN UB E CN UB 280DC 24 Format of the Meinberg standard time string 25 Format of the SAT time string 26 Format of the NMEA RMC string 27 Format of the time string...

Page 5: ...er s receiver A nominal constellation of 21 satellites together with 3 active spares in six orbital planes 20000 km over ground provides a minimum of four satellites to be in view 24 hours a day at ev...

Page 6: ...signal IF LO frequency RG58 cable up to 250 meters without additional amplifier IF circuit microcontroller correlator DCF77 simulation master oscillator D A converter Flash EPROM program memory GPS163...

Page 7: ...determination of the receiver s position on the globe A correction value computed from the satellites navigation messages increases the accuracy of the onboard TCXO to 5 10 9 and automatically compen...

Page 8: ...endently Timer mode Three on and off times per day per channel programmable Cyclic mode Generation of periodically repeated pulses A cycle time of two seconds would generate a pulse at 0 00 00 0 00 02...

Page 9: ...of leap seconds The coding sheme is given below M StartofMinute 0 1 s R RFTransmission viasecondary antenna A1 Announcementofa change in daylight saving Z1 Z2 Time zoneidentification Z1 Z2 0 1 Daylig...

Page 10: ...5 interface IRIG outputs Introduction The transmission of coded timing signals began to take on widespread importance in the early 1950 s Especially the US missile and space programs were the forces b...

Page 11: ...ignal 1 kHz carrier frequency BCD time of year complete date SBS time of day output level adapted IEEE1344 Code according to IEEE1344 1995 100pps AM Sine wave signal 1kHz carrier frequency BCD time of...

Page 12: ...12 IRIG standard format x 3x TYPICAL MODULATED CARRIER IRIG A 10000 Hz IRIB B 1000 Hz binary 0 binary 1...

Page 13: ...13 AFNOR time code format...

Page 14: ...e set during daylight saving time 64 Timezone Offset Sign sign of TZ offset 0 1 65 TZ Offset binary encoded 1 Offset from IRIG time to UTC time Encoded IRIG time plus TZ Offset equals UTC at all times...

Page 15: ...ion from which as much of the sky as possible can be seen The best reception is given when the antenna has a free view of 8 angular elevation above horizon If this is not possible the antenna should b...

Page 16: ...e after power up If the receiver position has changed by some hundred kilometers since last operati on the satellites real elevation and doppler might not match those values expected by the receiver t...

Page 17: ...onization and generatation of output pulses OCx LEDs The LEDs OC1 OC2 and OC3 on the left of the terminal block are indicating the status of the corresponding pulse output A burning LED symbolizes the...

Page 18: ...The contents of the program memory will not be modified until the loader program has sent the command to erase the flash memory So if the BSL key is pressed unintentionally the firmware will not be c...

Page 19: ...m battery on the board is at least 10 years If the need arises to replace the battery the following should be noted ATTENTION Danger of explosion in case of inadequate replacement of the lithium batte...

Page 20: ...on and valid almanac 12 minutes if invalid battery backed memory BATTERY BACKUP storage of pulse configuration and important GPS system data in the internal RAM backed up by lithium battery lifetime o...

Page 21: ...dard Meinberg SAT NMEA or Uni Erlangen NTP default settings COM0 19200 8N1 COM1 9600 8N1 Standard Meinberg time string per second mode of operation if sync TIME CODE OUTPUTS modulated via BNC connecto...

Page 22: ...rresponding optocoupler POWER REQUIREMENTS 19 72 VDC e g 3 6W DC insulation 1 5 KV DIMENSION 105 mm x 125 5 mm x 104 mm H x B x T CONNECTORS coaxial BNC connectors for antenna converter unit AM modula...

Page 23: ...575 42 MHz bandwidth 9 MHz CONVERTER local oscillator to converter frequency 10 MHz first IF frequency 35 4 MHz POWER REQUIREMENTS 12V 18V 100mA provided via antenna cable CONNECTOR coax type N female...

Page 24: ...24 Assembly with CN UB E CN UB 280DC Type N BNC male Type N male Type N male CN UB E 1 5m max Type N male GPS167 Antenna Meinberg GPS As short as possible...

Page 25: ...hours 00 23 mm minutes 00 59 ss seconds 00 59 or 60 while leap second uv clock status characters u clock has not synchronized after reset space 20h clock has synchronized after reset v different for D...

Page 26: ...day of the week 1 7 1 Monday hh mm ss the current time hh hours 00 23 mm minutes 00 59 ss seconds 00 59 or 60 while leap second zz time zone indicator Z MEZ European Standard Time daylight saving dis...

Page 27: ...ss seconds 00 59 or 60 while leap second ss fractions of seconds 1 10 1 100 A Status A time data valid V time data not valid bbbb bb latitude of receiver position in degrees leading signs are replaced...

Page 28: ...3 mm minutes 00 59 ss seconds 00 59 or 60 while leap second v sign of the offset of local timezone related to UTC oo oo offset of local timezone related to UTC in hours and minutes ac clock status cha...

Page 29: ...racter 20h n latitude the following characters are possible N north of equator S south of equator lll llll longitude of receiver position in degrees leading signs are replaced by a space character 20h...

Page 30: ...30...

Page 31: ...31 Diskette with Windows Software GPSMON32...

Page 32: ...submenu PC Comport in menu Connection Also transfer rate and framing used by the program are selected in this menu Communication between the clock and the PC comes about only if the GPS serial port is...

Page 33: ...rted by clicking the menu item Help in menu Help In every program window a direct access to a related help topic can be obtained by pressing F1 The help language can be selected by clicking the menu i...

Page 34: ......

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