Ansi C code
CodeGuru Home VC++ / MFC / C++ .NET / C# Visual Basic VB Forums Developer.com
Results 1 to 7 of 7

Thread: Ansi C code

  1. #1
    Join Date
    Oct 2010
    Posts
    11

    Ansi C code

    hello guys.recently i was away from the forum.I'M not c programmer and rarely i work with codes.

    I need some help about one subject. if you can help, I'll be very glad.

    There is one code, written with ansi c language. you can see the code at link:

    http://u1312.hizliresim.com/1j/6/v7tr7.png

    code is working there is no problem. but i need to change code to other comparasion type, because in my scada system, at same time, 30 same of this code is working at same time and it makes pc to run very very slowly. sometimes pc is freezing and I need to restart pc 4-5times every week. If I reduce the code number to 5 instead of 30, it works without problem, but 30 comparasion must take place at same time. If I change comparasion type I'm sure pc won't freeze ( not with c code, with dynamic comparasion).I just need to understand what code is doing.I posted question to Visual C++ because I could not see ansi c..

    As I understand code is reading one decimal number, and divides decimal number to 4096 if result is 1, then returned value is 1, if result is 2, return is 2... like this, return value becomes 0,1,2,4 or 8. but I'm not sure if I understood right.

    There is somewhere in code "expression = var1&61440" what is this for? 4096+8192+..= 61440 ok. but what the meaning? if you can describe what this code is doing exactly I'll be very happy.

    there is one code more.

    http://u1312.hizliresim.com/1j/6/v7ulx.jpg

    I need also understand this.expression = var1&768... 768 = 512+256 ok but why not 512+256+1024 ?

    if you can help I'll be very happy.

    I need a table like this.. if the read value is between

    0...4096> result 0,
    4097...8192 > result 1
    8192..12288> result 2
    12288...16384> result 4
    16384..32768> result 8
    ... I'M not sure if I made right table.

  2. #2
    Join Date
    Dec 2012
    Location
    England
    Posts
    2,389

    Re: Ansi C code

    Please post actual code and not unknown links. Many members (myself included) don't open links to unknown sites.

    Before posting, please format the code properly and use code tags. Go advanced, select the posted code and click '#'.
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  3. #3
    Join Date
    Oct 2010
    Posts
    11

    Re: Ansi C code

    ok you're right 2kaud. people may think it's not safe. here are the codes.

    Code1
    Code:
    #include "apdefap.h"
     long _main(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)
    {
    
    // Rueckgabewert
    int index;
    
    // Variable
    unsigned long var1;
    
    // Ausdruck 
    double expression;
    
    // Statuswerte
    unsigned long status[1];
    unsigned long quality[1];
    
    // Wertebereichsgrenzen
    static double limitValue[5] = {0.00000000000000,4096.00000000000000,8192.00000000000000,16384.00000000000000,32768.00000000000000};
    static unsigned long value[6] = {0,1,2,4,8,0};
    
    // Werte lesen 
    var1 = (unsigned long)GetTagDoubleStateQC (lpszObjectName,&status[0],&quality[0]);
    GetTagDoubleStateQC (lpszObjectName,&status[0],&quality[0]);
    
    // zu ueberwachender Ausdruck
    expression = var1&61440;
    
    // Aufruf der Ueberpruefungsfunktion
    index = Check_LimitsD (expression, 6, &limitValue[0]);
    
    return value[index];
    
    }
    Code2
    Code:
    #include "apdefap.h"
     long _main(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)
    {
    // Rueckgabewert
    int index;
    
    // Variable
    unsigned long var1;
    
    // Ausdruck 
    double expression;
    
    // Statuswerte
    unsigned long status[1];
    unsigned long quality[1];
    
    // Wertebereichsgrenzen
    static double limitValue[5] = {0.00000000000000,256.00000000000000,512.00000000000000,1024.00000000000000,2048.00000000000000};
    static long value[6] = {9539985,16711680,65280,255,255,9539985};
    
    // Werte lesen 
    var1 = (unsigned long)GetTagDoubleStateQC ( lpszObjectName,&status[0],&quality[0]);
    GetTagDoubleStateQC (lpszObjectName,&status[0],&quality[0]);
    
    // zu ueberwachender Ausdruck
    expression = var1&768;
    
    // Aufruf der Ueberpruefungsfunktion
    index = Check_LimitsD (expression, 6, &limitValue[0]);
    
    return value[index];
    
    }
    at code 2, 9539985 means gray, 16711680 means blue, 65280 means green and 255 means red. code2 is reading one decimal number and giving colour code as a result.

    but my question is; if the decimal value will be forexample 600 what will be result? For comparasion, I need to understand code is making which maths calculation, from 0 to xxx this colour, from xxx to yyy this colour.. I think you understood what I mean. I need to find out xxx yyy.

  4. #4
    Join Date
    Dec 2012
    Location
    England
    Posts
    2,389

    Re: Ansi C code

    And what do the functions do? You haven't included the source for them.
    All advice is offered in good faith only. You are ultimately responsible for effects of your programs and the integrity of the machines they run on.

  5. #5
    Join Date
    Oct 2010
    Posts
    11

    Re: Ansi C code

    forexample at code1,

    var1 = (unsigned long)GetTagDoubleStateQC (lpszObjectName,&status[0],&quality[0]);
    var1 is the source, it changes automaticly.. from 0 to 32768.when var1 = 10000, index becomes 2.

  6. #6
    Join Date
    Oct 2010
    Posts
    11

    Re: Ansi C code

    there is just somewhere left in the code that i did not understand. code1 is also working like this: I changed source, code is still working.

    Code:
    #include "apdefap.h"
     long _main(char* lpszPictureName, char* lpszObjectName, char* lpszPropertyName)
    {
    
    int index;
    
    unsigned long var1;
    
    double expression;
    
    static double limitValue[5] = {0.00000000000000,4096.00000000000000,8192.00000000000000,16384.00000000000000,32768.00000000000000};
    static unsigned long value[6] = {0,1,2,4,8,0};
    
    var1 = 10000;
    
    
    expression = var1&61440;
    
    index = Check_LimitsD (expression, 6, &limitValue[0]);
    
    return value[index];
    
    }
    this code gives value of 2.. when I change var1=8000; value becomes 1.


    I just want to understand this line.

    Code:
    expression = var1&61440;
    what is this doing? "&" means bitwise here?
    Last edited by pokajy; December 7th, 2013 at 03:16 PM.

  7. #7
    Join Date
    Oct 2010
    Posts
    11

    Re: Ansi C code

    ok ok I solved.

    61440 means 2#0000_0000_0000_0000_1111_0000_0000_0000
    10000 means 2#0000_0000_0000_0000_0010_0111_0001_0000

    if
    expression = 10000&61440;

    then.. expression = 2#0000_0000_0000_0000_0010_0000_0000_0000 = 8192

    if expression = 8192 then result is 2.
    ---------------------
    61440 means 2#0000_0000_0000_0000_1111_0000_0000_0000
    8000 means 2#0000_0000_0000_0000_0001_1111_0100_0000

    if
    expression = 8000&61440;

    then.. expression = 2#0000_0000_0000_0000_0001_0000_0000_0000 = 4096

    if expression = 4096 then result is 1.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


Windows Mobile Development Center


Click Here to Expand Forum to Full Width

This is a CodeGuru survey question.


Featured


HTML5 Development Center