Reading Weight from Weigh Bridge....

Question

Hi.
The scenario here is that we have to create module pool for picking up
the weights of trucks from weigh bridge ( AVERY brand ).
The existing system is in foxpro . Please find attached the text of AVERY guidance which exhaustively shows how the fox system is reading the
weight from the port, to which the weigh bridge is attached, on the
system kept at the location.
I wish to have the info regarding how, this functionality can be
achieved in ABAP as my perception is that this is not a simple
execution / run of an external program.
regards,
Suman
TEXT
getwt.prg
sample weight recieving program for Avery CTH
this is demo program for getting weight from the CTH
using the CALL and LOAD commands of dBASE III PLUS only.
This demo program demonstrates the use of LOAD and CALL commands
of dBASE III PLUS to get the weight from the CTH. The actual
program to get the weight is a file called GETCTH.BIN
To use GETCTH.BIN directly do the following:
   1. Start dBASE III PLUS normally.
   2. Type the command - LOAD GETCTH at the dot prompt of dBASE III PLUS.
      (Be sure to give the correct drive and/or directory where the
       file GETCTH.BIN resides in your computer system).
   3. The program GETCTH.BIN will return the weight in a variable
      passed from dBASE III PLUS, so first initialize a variable in
      dBASE III PLUS to recieve the weight.
      The weight string returned by the CTH is 26 charecters long so
      define a variable of length 26 by typing the following command
      at the dot prompt:
      WEIGHT = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"   { Any dummy value }
                            or
      WEIGHT = "2BCDEFGHIJKLMNOPQRSTUVWXYZ"   for COM2 port
      ( Note -> The choice for the name of the above variable is
                purely arbitrary. Any name could have been chosen)
   4. Next type the following command at the dot prompt to call the
      GETCTH function :
      CALL GETCTH WITH WEIGHT
   5. After some time the dot prompt will return. At the dot prompt
      type the following :
      ? WEIGHT
      If the GETCTH function has been successfull in getting the weight
      from the CTH then this function will return the weight as a string
      of 26 charecters containing the weight and other information.
      Otherwise, if the function is not successfull then the value of
      the variable passed will be set to 26 spaces. The major reason
      for the failure of the function will be a timeout error i.e.
      the CTH did not respond after a preset time interval had elasped.
      The returning of 26 spaces makes it easy for a dBASE III PLUS
      program to retry the weighing operation if failure is detected.
      The use of this in a loop till the function succeeds in getting
      a weight is illustrated below in the program.
      The weight returned by the CTH consists of a string of 26 charecters
      A sample weight that could be returned is reproduced below:
      ABCDEFGHIJKLMNOPQRSTUVWXYZ
        19600 kg    G 000016 O
      The following is the sequence of charecters :
      1. The first two charecters ( positions A - B above ) are
         space charecters.
      2. The next five charecters ( positions C - G above ) is the
         weight from the CTH - ( 19600 in this case).
      3. The next charecter ( position H above ) is a space charecter.
      4. The next two charecters ( positions I - J above ) are the weight
         units - ( kg in this case ).
      5. The next four charecters ( positions K - N above ) are space
         space charecters.
      6. The next charecter ( position O above ) specifies mode of
         operation. It shows 'G' for Gross mode and 'T' for Tare
         mode of operation.
      7. The next charecter ( position P above ) is a space charecter.
      8. The next six charecters ( positions Q - V above ) is the
         consecutive number which is unique for each weighing.
      9. The next charecter ( position W above ) is a space charecter.
     10. The next charecter ( position X above ) is the machine ID number.
     11. The last two charecters ( positions Y - Z above ) are
         Carriage return and Line feed charecters.
Clear the screen and show the copyright notice.
clear
@  0,  0  TO 23, 79    DOUBLE
@  3,  1  TO  3, 78
@ 11, 25  TO 18, 57
set color to w/n+
@  1, 26  SAY "A V E R Y     I N D I A   L I M I T E D"
set color to
set color to n/w+
@  2, 10  SAY " Demo program for getting weight from Avery weight digitiser - CTH "
set color to
set color to w/n+
@  6,  3  SAY "(C) Avery India Ltd.- 1989,1990  All rights reserved."
@  8, 10  SAY "The source code of this program is for pure demo purposes and all"
@  9, 10  SAY "copyright  of   this    demo  program  and  its source rests with"
@ 10, 10  SAY "Avery India Ltd."
@ 20, 10  SAY "This program and its  accompaining  source  code cannot  be  used"
@ 21, 10  SAY "without the prior permission of Avery India Ltd."
set color to
set color to n/w+
@ 17,26 say " Press any key to continue...  "
set color to
wait ""
@ 4,0 clear to 23,79
@ 0,0 to 19,79 double
WEIGHT = space(26)                && define a variable to get the weight
load getcth                       && load the module from disk
                                  && this assumes that the file GETCTH.BIN
                                  && is in the current drive/directory.
                                  && If not, use drive specifier.
do while weight = space(26)       && the main loop
   call getcth with weight
enddo
set color to w/n+
As explained above the last two charecters of the weight string
are the Carriage return (CR) and the Line feed (LF) charecters
out of the total of 26 charecters of the weight string. So to get
the whole weight string other than these last two chareceters we
can use the SUBSTR command of dBASE III PLUS as follows :-
  @ 14,20 say "The weight is : " + substr(weight,1,24)
This will show the whole weight string on the screen i.e. all
24 charecters ( it will not show the CR and the LF charecters ).
The CR and the LF charecters are as it is unprintable charecters
and will show up as control charecters if printed on the screen.
If the whole weight string is not required and only, say, the
weight and the weight units are required, then the following command
could be used :-
@ 14,20 say "The weight is : " + substr(weight,1,10)
This will show the weight value and the weight units (this substring
will include the embedded space charecters in this susbtring).
Similarly, other parameters from the weight string could be
incorporated, if required, from the whole string to enhance
the weighing process on the computer.
The idea of putting the CALL statement above in a loop is that
sometimes due to unavoidable reasons, there may some garbage
charecters on the serial port. Thus it may be necessary to flush these
charecters from the port by CALLing the function again.
Sometimes, the function may return without a timeout error but the
variable may contain some control charecters which do not make sense.
In this case the function should called repeatedly till the proper
charecters are returned. This occurs due to the reason explained
above.
@ 14,20 say "The weight is : " + substr(weight,1,24)
set color to
set color to n/w+
@ 16,5 say "Please read the README.DOC file on this disk for more information"
release module getcth             && release module from memory
set color to
Please refer to the dBASE III PLUS manuals for a
complete discussion on the LOAD, CALL and RELEASE
commands.
Message was edited by: Suman Tyagi

Answer 1

Thanks, but I've already seen this thread and done the steps described on it.
Actually, my question is very specific... How to populate the fields LinkVal and LinkUnit of the registry...
I read all the threads here in SDN and they don't answer my question...
I'd be glad if someone had already done tcode HUPAST works for Filizola...
Tks again.