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					     OPERATING

WITH PM46 V3.6



               MED-HYCOS CRP
                      C/O IRD
    B.P. 5045 - 34 032 - Montpellier - France
Tél : (33) 4 67 63 64 20 Fax : (33) 4 67 41 21 33
          Email : Marc.Morell@ird.fr
           http : //medhycos.ird.mpl.fr
                                                                    SUCCINT




ARCHITECTURE................................................................................................................................................. 3




ACQUISITION.FUNCTION................................................................................................................................ 6




MEMORY CARD ................................................................................................................................................. 7




METEOSAT MESSAGE. ................................................................................................................................... 13




                                                                                                                                                             2
        Architecture.




                        RAM 1    RAM 2

                        128 Ko   128 Ko



         Microp
PROM
          80186
         16 MHz
256Ko



                            MEMO CARD
                               1 Mo




                                          3
                      DATA BASE
                          P


                      STATISTICS
                    COMPUTATION
                    EVER P PERIODS

                                         METEOSAT
    ACQUISITION
                                            T
         S

        DATA                             METEOSAT
⇒    ACQUISITION                         MESSAGE
⇒   FROM SENSORS                        TRANSMITED
⇒   EVER S PERIOD                        AT PERIOD
⇒                                          T = 3h
                       MEMORY
                         E


                    DATA RECORDING
                    DURING P PERIOD   MEMO
                                      FLASH




                                                     4
                                  PERIODS



S : SCRUTATION PERIOD

Threshold parameters are examinated at the end of this period.
Related for each sensor


P : REPRESENTATIVITY PERIOD

Period where are elaborate computation on S period samples.
Related for all sensors


E : STORAGE PERIOD

Data are stored on memory card at the end of this period.
Related for all sensors


T: METEOSAT PERIOD

Set in factory to three hours


DEFAULT VALUES:

S = 1mn ou 1h
P=1h
E=3h


PERIOD RANGE

S:    1, 6, 15 , 30 mn, 1, 3, 6, 12, 24 h

P:    30 mn, 1, 3, 6, 12, 24 h

E:    30, 60 mn, 3, 6, 12, 24 h


                                                                 5/20
                            Acquisition function.




Sensors acquisition is realised on their own scrutation period S.

A general acquisition is done on all the sensors when there is a storage of the
header in the memory card. This acquisition is realised by the written of the
identification station number on the memory card.

Others acquisitions can exist. For exemple, when the operator need to modify
the water level value or when you have to modify the voltage battery value.

Acquisitions are limited to 190 by representativity period P.
This limitation is compulsery because of the internal RAM (buffer) capacity.
If this limitation is reached for one sensor, at the next acquisition all the
previous acquisition will be lost.




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                                 Memory Card

Based on Flash type, these memory cards are waterproof, removable,
contactless and so very resistiv to humidity, temperature…
No battery is needed to keep on the data.
On MED-HYCOS modules have a capacity of 1 Mo

For each sensor you have a scrutation period S and a programmable threshold or
difference value which constitues the decisive storage criterion.
The data is stored at S if :
       -the difference between the measured value (at S) and the previous value
       measured (at S-1) stored on the memory card is greater than the
       programmed difference.
                                           OR
       -the difference between the measured value and the previous value
       measured (but not recorded !) is greater than the programmed difference.

The threshold can be put to zero and in this case all measured values are stored.
By default, the storage period is put to E=3h.


Measures record are:

      - HH : water level              encoded in cm
      - TT : Water temperature        encoded in 0,1 °C         signe is
      - RR : rainfall                 encoded in 0,1 mm                put in front
of
      - TA : Air temperature          encoded in 0,1 °C        the value.

First, messages are stored in temporary RAM (Buffer)
At the end of the E period or if the buffer is full, messages are directed to the
memory card. This way of working limit the energy consumption.
But this is totally transparent to the operator.




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Storage format is :

              - identification station number : IDENT 5 bytes ( 00000 to
              99999) suit to a blank character
       then a measures block :
       - date and time : AAMMJJ HH:MN 12 bytes suit by a blank character
       - Sensor label and channel number on 4 bytes suit by a blank character
       - Measure in the format defined for each sensor.
       A blank character separate each value.
       The measures block is ended by characters CR LF

Exemple for a complete message is given under:
AAMMJJ HH:MN HHnn+yyyy TTnn+yyy RRnnyyyyyy TAnn+yyy CRLF


Storage conditions

At each acquisition time, there is a computation of the difference between the
measured value and the measured value done at last S period and the value
stored; there is a comparison of this difference with the programmable threshold
and there will be storage of the value if the difference is enough
There is no test on water température which is stored automatically with the
water level measurement.
There is no storage threshold for rainfall which is recorded automatically if a
impulse appears.

When operator switch on the DCP, when he erase or change the memo card, the
first written on the memo card is the station identification number which
become the header. After that you have a measurement of all sensors
(acquisition without conditions).
       Memory card storage data exemple:

12345                                                    Station identification
960528 11:05 HH25 +0007 TT25 +216 RR15 00000 TA01 +210   General acquisition
960528 12:00 RR15 000010                                 Rainfall
960528 15:00 RR15 000030
35564                                                    New station identification
960528 15:11 HH25 +007 TT25 +216 RR15 000030 TA01 +210   General acquisition
960529 12:00 TA01 +218                                   Threshold exceeded for TA sensors




                                                                                             8/20
The station identification number is written at the switch on of the station. By
default the value is 00000.

00000                               Default station identification
12345                               Operator enter the real station identification.
960528 11:05 HH25 +0007 TT25 +216 RR15 00000 TA01 +210          General acquisition


If you want to avoid this double header storage, you can select to erase the
memory card after switch on and enter the real value. Be careful not loose still
storage data.

When you change a memory card, you don't have to enter again the station
identification number. This is done automaticaly by the program (in the "Card
switch on" menu) like the general acquisition on all the sensors




                                                                                      9/20
Values measured by the differents sensors :

Threshold exceeded on the differents sensors at the same minute are put on the
same record line.
Ex :

12345                                                      Station identification number
960528 11:05 HH25 +0007 TT25 +216 RR15 00000 TA01 +210     General acquisition
960528 12:00 RR15 000010                                   Rainfall
960528 16:00 TA01 +217                             Threshold exceed on TA sensor
960528 17:00 HH25 +0001 TT25 +216                  Threshold exceed on HHTT sensor
960528 18:00 RR15 000030 TA01 +218                 Threshold exceed TA sensor and rainfall
960528 19:00 HH25 +0005 TT25 +216 RR15 000040      Threshold exceed on HHTT sensor and rainfall


The DCP must wait the end of the minute to store data on the buffer. So the
measurements acquire at the E minute work will be store at the next E period.



Differents length of messages :

       - sensor RR alone : 26 characters,
       - sensor TA alone : 24 characters,
       - sensor HHTT alone : 35 characters,
       - sensors RR and TA : 36 characters,
       - sensors RR and HHTT : 47 characters,
       - sensors TA and HHTT : 45 characters,
       - sensors RR, TA and HHTT : 57 characters,

When the memory card is changed or erased, the buffer is empty. So measures
again in buffer before this modification will be lost.
If the buffer is full during a data storage into, it will be erase to receive the new
data.




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Memory card autonomy :

It depends of :
      - memory card capacity, here 1 Mo (1024000 octets)
      - scrutation périod S.
      - storage threshold definition.

If we want to find the minimum autonomy, the critical case is a complete
written on memory card every minute 54 bytes/minute.
In this case we have 1440*54 bytes / day so the autonomy is
1024000/(1440*54) = 13 days


E period:

Storage period E can be change by the keyboard of the DCP.
Operator can choose differents periods.
By default the E period is 3H. If you put another value, this new period will be
operationnal after the last period operation.



Full memory card :

When the DCP is initialized if the memory card is not empty, then storage on
this card is impossible. The operateur must erase or change the card.
The card is full when there is not enough place to store a block record of 500
characters.




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Reading of memory card :

The cards are read in the laboratory using a PC type computer and the reader
supplied. The reader requires a 220 Volt AC power supply and connects to the
COM1 or COM2 serial ports of the computer.
Begin by installing the reading software on the computer, by running
A: INSTALL.
The sotware is stored in the MCARD directory.
Run MDRIVE H and you will obtain the list of Read or Erase options that are
available.
The reader reads the contents of the card and tranfers it to a text file.

      Differents options are available :
Ax    : select the beginning of the data adress /x =in HEX
Bx    : select tranfer speed / x = 115200, 38400, 19200, 9600 Baud
Cx    : select serial port / x = 1,2,3 ou 4
E     : Erase data
Fx    : Define the name of the text file./ x = file name
Nx    : Define the length of the text file / x= bytes numbers in HEX
Rx    : Read the data and record them in the file x

By default the configuration of MDRIVE is :
      - A00
      - B115200
      - C1
      - RMDRIVE.TXT

Now a Windows software is available : Memowin.




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                            METEOSAT Message

Meteosat message is encoding in WMO CREX code.
CREX : Character Form for the Representation and Exchange of data
This encoding format can simplify international data exchange by using simple
list of values.

Message is send every 3 H to the satellite.

This message is done by three meteo messages, hourly separate.

Exemple of CREX messages

CREX++
T0000101 A000 D05009 ++             ⇒ Header line
68019 0 1996 07 02++                ⇒ Station identification line
08 00 60 0003++                     ⇒ Definition line
0348 0294 0004 3381 0000 00019 ////+     ⇒ measures n°2 (heure H)
0349 0294 0000 3380 0000 00014 ////+     ⇒ measures n°1 (heure h-1)
0349 0294 0005 3379 0000 00014 ////+     ⇒ measures n°0 (heure H-2)
7777++0119 027 0016 097 /// /// 0 V3.6                 ⇒ End Of Message ++
                                                       Maintenance
                                                       parameters line.




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      CREX Code

      Header line CREX++
      Data description line T000101 A000 D050XX++
      Identification line define by code D01029
      Measures definition line define by codes D01012, B0465 et R01000
      Measures number 1 defined by code D05XXX
      Measures number 2 defined by code D05XXX
      Measures number 3 defined by code D05XXX

                                                                                          Length
                                                                                 Units
                                                                                          (Bytes)
                           B01018 :   WMO station identification                            5
                           B02001 :   Station type                                          1
            D01029
                                      B04001 : Year                                         4
          Identification    D01011
                                      B04002 : Month                                        2
                             Date
                                      B04003 : Day                                          2
                           B04004 :   Hour of the first line of measurement                 2
             D01012
              Hour
                           B04005 :   Minute of the first line of measurement               2
       B04065 : Hour step                                                       minutes     2
D05009 R01000 : Number of measurement (n=3)                                                 4
                                    B13072:       Water level                     Cm        4
                            D05006 B1308:         Water Temperature              0,1 K      4
            D05008                  B13019:       Last hour rainfall            0,1mm       4
                             One    B12073        Air temperature                0,1 K      4
         Measure lines      measure B13073        Maximum water level (on P)      Cm        4
                              line  B13060        Total cumulative rainfall     0,1 mm      5
                                    B12031        Soil temperature               0,1 K      4
            D05008




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   METEOSAT messages description


Definition of the differents lines :

       –Header line :                         CREX++

This line has 8 characters with characters 'CR' et 'LF'.


       —Data description line :

                                  T 0 0 0 1 0 1            A 0 0 0   D 0 5 0        + +
                                                                               XX

N° of the CREX table (00 = Table
CREX standard (WMO FM 95))
Tables edition
CREX code version

A table reference corresponding to CREX format

Code number of the table D reference
(class 5 : Hydrology and Meteorology)
Sequence number in class 5 to describe data format

This line contains 23 characters, with characters 'CR' et 'LF'.




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        ˜Identification station line:

                                           4 0 1 2 4          0          1 9 9 6      0 7     0 2 + +

Identification station number

Station type

              DATE                          Millenium
 (date of the last meteo message            Year
            at H hour)                      Month
                                            Day

This line contains 22 characters, with characters 'CR' et 'LF'.


        ™Definition line:

                                             0 1        0 0        6 0       0 0 0 3 + +

     Hour of the last            Hour
     Meteo message
           H                     Minute

Representativity period (in minutes) of each message

Number of meteo message in the message

This line contains 17 characters, with characters 'CR' et 'LF'.

        šMeasure Line :

                                             0001   0002          0003     0004    0005   00006   0007+

Last Water level (in cm)

Last water temperature (in 0,1 K)

Rainfall cumul during P periode (in 0,1mm)

Last Air temperature de l'air (in 0,1 K)

Maximum of water level on P period (in cm)

Last total cumulative rainfall (in 0,1mm)

Last Soil temperature du sol (in 0,1 K)




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With characters 'CR' et 'LF', this line contains 38 characters minimum to 40 characters maximum when all
signed values are negatives.
The sign appears only if the measure is negative.
Rainfall and Kelvin values are never negative.

All these measures are done during the P period. So we have 3 meteo messages (3 line of measures)
And all the values are dated at fixed hours spaced of 3 hours.



         šMeasures line :

                                   7777++      0001      002       0003   004    005      006       0      V03.06

Average of battery voltage (en mV)

Solar panel utilisation in percent

Average of electronic card temperature (en °C)

Non used capacity memory (en %)

Average on a 4/20 mA sensor in channel n°3 (in mA)

Average on a 4/20 mA sensor in channel n°4 (in mA)

Indication on DCP function since the last emission

Software version number

With characters 'CR' et 'LF', this line contains 42 to 43 characters.

The indicator on DCP function say if there was a reset (=1) or not (=0) since the
last emission.
If there was a reset, the operator must be careful with data.


Remarks : For no present sensors, values are replaced by characters /
          The length of the CREX message can go from 226 to 233
          characters.




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Particular case :

It can be exist that the message is not complete

       - Unknow measure on entire period :
At the first time of DCP initialization, the number of meteo message can be
different of 3.
In this case, messages are replaced by ///// . And there is a drift of the line and
the corresponding hours.

So:
- H hour line contains :
      //////////////////// if there is less than 3 meteo messages.
- H-1 hour line contains :
      H measurement if there is 2 meteo messages
      or //////////////// if there is one or none meteo message.
- H-2 hour line contains :
      H-1 measurement if there is 2 meteo messages
      or H measurement if there is only one meteo message
      or ///////////////// if there is no meteo message.
This case is only possible after a reset or DCP switch on, or if all sensors break
down together.

Ex : DCP switch on at 01:30:00
      Transmitter ask for the message of 03:00:00
      Two messages are download (at 02:00:00 and at 03:00:00; the 01:00:00
doesn't exist)

CREX message will be :
CREX++
T000101 A000 D05009 ++
68019 0 1996 07 02++
03 00 00060 00002++                            ⇒ 2 meteo messages
//// //// //// //// //// ///// +
0348 0294 0004 3381 0000 00019 ////+           Hour H
0349 0294 0000 3380 0000 00014 ////+           Hour H-1
7777++0119 027 0016 097




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If there is no message all the measurement lines and date lines will be replaced
by ////////.
Identification station, date, P period and maintenance parameters will be
replaced by ////// because they depend on the last measurement which is
unknow.

Ex :
CREX++
T000101 A000 D05009
/ / / / / 0 / / / / / / / / ++
/ / / / 00060 00000++
//// //// //// //// //// ///// +
//// //// //// //// //// ///// +
/ / / / / / / / / / / / / / / / / / / / / / / / / ++
7777++ / / / / 001 / / / / / / / 0


       - Unknow measures for out of order sensors :
If a sensor falls down, his data are replaced by ///////

CREX++
T000101 A000 D05009 ++
68019 0 1996 07 02++
08 00 00060 00003++
0348 0294 0004 3381 0000 00019 ////+
0349 0294 0000 / / / / 0000 00014 ////+                ⇒ TA Sensor break
0349 0294 0005 / / / / 0000 00014 ////+                ⇒ at hours H-1 et H-2
7777++0119 027 0016 097


If a sensor falls down at H hour and even if it has work at H-1 and H-2, all his
data will be replaced by ////.

CREX0101 A000 D05007 ++
68019 0 1996 07 02++
08 00 00060 00003++
0348 0294 0004 / / / / 0000 00019 ////+                ⇒ TA Sensor TA break at H
0349 0294 0000 / / / / 0000 00014 ////+
0349 0294 0005 / / / / 0000 00014 ////+
7777++0119 027 0016 097




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MED-HYCOS DCP don't have soil temperature sensor so each measurement
line end by ////+

CEIS-TM transmitters give 3 bytes of data (independant measures done on
transmitter itself) related to his voltage, his internal temperature, his power and
channel frequency.




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