Unit can't get value from other unit
lazarus / 9-Editor

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Paul-SFL · 2011-11-05 20:54

Hi all,
I'm asking for someone's help 'cause I've already got mad trying to
solve my problem  .

I'm working on a program which emulates a simple processor. It
consists of several units.

All variables are placed into separate unit, another unit is the
emulator itself and the third one is a form where I need to output
contents of the processor's "registers" to on each step of emulation.
Emulator is 100% working. The problem is that when I try to output the
data it doesn't work properly - form's field where I put value of
register variable to gets wrong value.
I don't know what information is necessary and what's not.. Here is
code which outputs the value from one of registers:

Code: [Select]procedure ]"]>Blockedlator_mode.traceClick(Sender:
TObject); //emulgui's procedure
var CRstring:bstring    ;
begin
  step; //performs one emulation step; testprocessing's procedure
  Set2Str(TCV.CR,CRstring); //converts set to string; testprocessing's
procedure
  emulator_mode.CR.Caption:=CRstring; //moves string to TLabeledEdit's
caption
end;
I guess maybe I made a mistake in units referrence.. Here it is:

Code: [Select]unit emulgui //window where I need to output data

interface

uses tcv //unit where all variables, types and constants are

implementation

uses testprocessing //emulation unit
Code: [Select]unit testprocessing

interface

uses tcv;

implementation

uses emulguiIs that right?
Using Lazarus 0.9.30 wih FPC 2.4.2 on Windows 7 Professional.

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Blaazen · 2011-11-05 21:08

I can't see anything wrong with your code snippets.

Quote- form's field where I put value of register variable to gets
wrong value.
What it means "wrong value" ? Is it empty, bad format or ... ?

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Paul-SFL · 2011-11-05 21:26

Wrong means value that shouldn't be there.

CR.Caption must get certain values - they're in txt file. The value
CR.Caption gets is not present in that file..

Txt file includes strings with quaternary numbers (they mean commands
and numbers). Testprocessing unit reads them, converts to strings with
binary numbers, then to sets, then moves them to RAM variable (array
of sets). Procedure TestLoading which performs all this is called from
emulgui unit on form create.

In Step procedure program reads next set from RAM to CR (set
variable), then performs some (depends on CR value) processor's
operation emulation.

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Leledumbo · 2011-11-06 01:54

Then we need to see Step and Set2Str implementation. Or you could
place a breakpoint:
Code: [Select]procedure ]"]>Blockedlator_mode.traceClick(Sender:
TObject); //emulgui's procedure
var CRstring:bstring    ;
begin
  step; //performs one emulation step; testprocessing's procedure
(* PUT BREAKPOINT HERE *)  Set2Str(TCV.CR,CRstring); //converts set to
string; testprocessing's procedure
  emulator_mode.CR.Caption:=CRstring; //moves string to TLabeledEdit's
caption
end;and inspect the changes yourself.

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Paul-SFL · 2011-11-06 07:21

Oh, I'm not very familiar with breakpoints and Lazarus debugger on the
whole..

Here is procedures implementation:
Code: [Select]Unit testprocessing;

{$mode objfpc}{$H+}

Interface
Uses tcv;

procedure Set2Str(Const Word_:set_14; Var NewStr:bstring);
procedure TestLoading(TestNum:byte);
procedure Step;
procedure OpCodeDC;
procedure CRDC;
Procedure CommandLoading;
procedure g1halt;
procedure g1load;
procedure g1save;
procedure g1add;
procedure g1sub;
procedure g1mul;
procedure g1div;
procedure g1subm;
procedure g1and;
procedure g1or;
procedure g1xor;
procedure g1inc;
procedure Bin2Qua(Const BinNum:bstring; Var QuaNum:qstring);
procedure Qua2Bin(Const QuaNum:qstring; Var BinNum:bstring);
procedure Bin2Dec(Const BinNum:bstring; Var DecNum:dstring);
procedure Dec2Bin(Const DecNum:dstring;Var BinStr:bstring);
procedure Str2Set(Const Str:bstring; Var NewWord:set_14);
procedure Dec2Set(DecNum:integer; Var Set_:set_14);
procedure Set2Dec(Set_:set_14; Var DecNum:integer);
procedure Set_8ToSet_14(Const R:set_8; Var Set8Converted:set_14);
procedure Set_14ToSet_8(Const R:set_14; Var Set14Converted:set_8);
procedure AR2Dec;

Implementation
Uses emulgui;

Procedure Set2Str(Const Word_:set_14; Var NewStr:bstring);
Var
  i:byte;
Begin
  NewStr:='00000000000000';
  For i:=1 to BinNumLen do
    If i in Word_ then
      NewStr[i]:='1'
End { Set2Str };
{ ========================== }
Procedure TestLoading(TestNum:byte);
Var
  Test :text;
  Code:integer;
  RawSA:string[3];
  QuaStr:qstring;
  BinStr:bstring;
  NewWord:set_14;
  i:byte;
Begin
  If Test1Loaded then //procedure is temporary tied to the test №1
    Exit;
  Case TestNum of
    1 : Assign(Test,'test1.txt');
    2 : Assign(Test,'test2.txt');
    3 : Assign(Test,'test3.txt');
  End;
  Reset(Test);
  Readln(Test,RawSA);
  Val(RawSA,SA,Code);
  RAM[0]:=[];
  i:=1;
  While not EoF(Test) do
    Begin
      Readln(Test,QuaStr);
      Qua2Bin(QuaStr,BinStr);
      Str2Set(BinStr,NewWord);
      RAM[i]:=NewWord;
      Inc(i)
    End;
  Close(Test);
  Case TestNum of
    1 : Begin
          Test1Size:=i-1;
          Test1Loaded:=true;
          Test2Loaded:=false;
          Test3Loaded:=false
        End;
    2 : Begin
          Test2Size:=i-1;
          Test1Loaded:=false;
          Test2Loaded:=true;
          Test3Loaded:=false
        End;
    2 : Begin
          Test3Size:=i-1;
          Test1Loaded:=false;
          Test2Loaded:=false;
          Test3Loaded:=true
        End;
  End;
  SAinIP:=false;
End { TestLoading };
{ ========================== }
Procedure CommandLoading;
Var
  Buf  :set_14;
  var crc:bstring    ;
Begin
  If not SAinIP then
    Begin
      Buf:=[];
      Dec2Set(SA,Buf);
      Set_14ToSet_8(Buf,IP);
      SAinIP:=true
    End;
  AR:=IP;   
  Set_8ToSet_14(AR,Buf);
  Set2Dec(Buf,ARVal);
  WR:=RAM[ARVal];
  CR:=WR        ;
End { CommandLoading };
{ ========================== }
Procedure CRDC;
Var
  i:byte;
Begin 
  With CRDecoded do
    Begin
      OpCode:='0000';
      DestRegister:=0;
      AddrMode:=0;
      Address:='00000000000000';
      For i:=1 to 4 do
        If i in CR then
          OpCode[i]:='1';
      If 5 in CR then
        Inc(DestRegister);
      If 6 in CR then
        Inc(AddrMode);
      For i:=7 to BinNumLen do
        If i in CR then
          Address[i]:='1'
    End;
  g1Inc
End { CRDC };
{ ========================== }
Procedure OpCodeDC;
Var
  OpCode,
  Code    :integer;
Begin
  Val(CRDecoded.OpCode,OpCode,Code);
  Case OpCode of
     0 : G1Halt;
     1 : G1Load;
     10 : G1Save;
     11 : G1Add;
     100 : G1Sub;
     101 : G1Mul;
     110 : G1Div;
     111 : G1Subm;
     1000 : G1And ;
     1001 : G1Or  ;
    1010 : G1Xor ;
    1011 : G1Inc ;
    (*1100 : JS_  ;
    1101 : JZ_  ;
    1110 : Jump_;
    1111 : Call_*)
  End
End { OpCodeDC };
{ ========================== }
Procedure Step;
Begin
CommandLoading;
CRDC;
OpCodeDC;
End { Step };
{ ========================== }

End.

Hmm, just tried to run debugger (pressing F8) and got an error saying
"Project gui1.exe called exeption class 'External: SIVSEGV'...

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User137 · 2011-11-06 08:05

Is BinNumLen a constant value 14? Counted 14 zeroes in NewStr...
Propably helps showing also set_14 type definition.

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Paul-SFL · 2011-11-06 08:42

Yes, BinNumLen is constant value 14
Code: [Select]Type
  fourteen_elems=1..14;
  set_14=set of fourteen_elems;

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User137 · 2011-11-06 09:08

Code: [Select]var s: string; w: set_14;
begin
  s:='';
  w:=[6,5,3,13,14, 15,0,-6,99]; // Add 5 bits and some extras outside
range
  Set2Str(w, s);

// Now s = '00101100000011'; which seems correct
Could it be that values themselves that are delivered to Set2Str() are
wrong?

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Paul-SFL · 2011-11-06 09:25

No, it doesn't seems to be so. All procedures have been tested many
times. 

Set2Str() checks only correct values (1..14), so output string cannot
include wrong values:
Code: [Select]  NewStr:='00000000000000';
  For i:=1 to BinNumLen do //i gets only values from 1 to 14
    If i in Word_ then
      NewStr[i]:='1'
Generally speaking, the program is being written in purpose that all
input data is correct.

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Leledumbo · 2011-11-06 13:14

QuoteHmm, just tried to run debugger (pressing F8) and got an error
saying "Project gui1.exe called exeption class 'External:
SIVSEGV'...Then you're one of people who get problem with the
debugger, happily search the forum. The cause varies, though.

If you're not familiar with the debugger, you can use 'old ways' of
debugging: put ShowMessage on curious points (loops, branches, etc),
displaying the contents of variables whose value seems not right.

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Paul-SFL · 2011-11-06 13:55

Leledumbo, thanks, I get it. I'll try..

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Paul-SFL · 2011-11-11 15:47

Oh, guys, what a stupid mistake I made  ...

Testprocessing unit was tested in Turbo Pascal (as I'm yet not very
familiar with FPC), and I tested it as a single program, without
separating to units.

When I started adding Testprocessing and TCV to Lazarus project, I
simply copypasted code (unit declaration, to be exact) from emulgui,
and there this string was:
Code: [Select]{$mode objfpc}{$H+}
The solution was replacing {$mode objfpc} with {$mode tp} in
Testprocessing and TCV units.

Thank all for your advice  .