It's a crazy story

[hamradio]

Try this code:

Code: Select all

// *
// * Project name:
//    Soft_Uart_Test
// * Copyright:
//     (c) mikroElektronika, 2006
// * Revision History:
//     20060922:
//       - initial release.
// * Description:
//     This code demonstrates how to use usart library routines. Upon receiving
//     data via RS232, PIC MCU immediately sends it back to the sender.
// * Test configuration:
//     MCU:             PIC18F4520
//     Dev.Board:       EasyPIC4
//     Oscillator:      HS, 20.000 MHz
//     Ext. Modules:    none.
//     SW:              mikroPascal v8.1
// * NOTES:
//     - make sure you switch ON RC7 and RC6 (board specific)
// *

program Soft_Uart_Test;

var i, pos, read_error : byte;
    L0, L1, L2, L3, L4, L5, L6, L7, txt : string[20];
    ricevuto, x : string[1];
    

procedure print_display;
begin
Glcd_fill(0);
glcd_Write_Text(L0, 0, 0, 1);
glcd_Write_Text(L1, 0, 1, 1);
glcd_Write_Text(L2, 0, 2, 1);
glcd_Write_Text(L3, 0, 3, 1);
glcd_Write_Text(L4, 0, 4, 1);
glcd_Write_Text(L5, 0, 5, 1);
glcd_Write_Text(L6, 0, 6, 1);
glcd_Write_Text(L7, 0, 7, 1);
end;



procedure nuova_freq;
begin
L7 := 'input start';
txt:= '';
pos := 0;
ricevuto := '';
x := '';
L0:= '';
L1:= '';
print_display;
end;

procedure end_input;
begin
L7 := 'input end';
print_display;
end;

Procedure byte2ascii;
begin
case i of
  48 :  begin
        ricevuto := '0';
        inc(pos);
        end;
  49 :  begin
        ricevuto := '1';
        inc(pos);
        end;
  50 : begin
        ricevuto := '2';
        inc(pos);
        end;
  51 :begin
        ricevuto := '3';
        inc(pos);
        end;
  52 : begin
        ricevuto := '4';
        inc(pos);
        end;
  53 : begin
        ricevuto := '5';
        inc(pos);
        end;
  54 : begin
        ricevuto := '6';
        inc(pos);
        end;
  55 : begin
        ricevuto := '7';
        inc(pos);
        end;
  56 : begin
        ricevuto := '8';
        inc(pos);
        end;
  57 : begin
        ricevuto := '9';
        inc(pos);
        end;
        
  63 : nuova_freq;
  
  42 : end_input;
        
  end;

end;

Procedure elabora_input;
begin
L0 := 'elab_input';
byte2ascii;
strncat2(L1, ricevuto);
print_display;
//if pos >7 then end_input;
end;






begin
   ADCON1 := 15;
   Soft_Uart_Init(PORTC, 7, 6, 19200, 0);       // Initialize Soft_UART module
   trisa := 0;
   trisb := 0;
   trise := 0;
   Glcd_Init(portb, 0, 1, 2, 3, 5, 4, PORTd);
   Glcd_fill(0);
   //Glcd_set_font(@fontsystem5x8, 5, 8, 32);
   pos := 0;
   txt :='';
   L0 := '';
   L1 := '';
   L2 := '';
   L3 := '';
   L4 := '';
   L5 := '';
   L6 := '';
   L7 := 'elefante';
   ricevuto :='';

   while true do
     begin
       i := Soft_Uart_Read(read_error);         // Read the received data, blocking call.
       Soft_Uart_Write(i);                      // Send data back via UART.
       elabora_input;


    end;

end.

Input by terminal only number 0 to 9 or * or ?

Nothing happen on the display the sent caaracters isn't shows on display and aren't echoed to terminal.


Now go to procedure "nuova_freq" and commented the line "x := '';"

Now all work fine.

I have changed the x's variable name in many manner but the code don't operate until I comment the line.

No error is show by compiler.

Have anyone a expalin why this happen ?

Thanks Carlo

[yo2lio]

String[1] ?????

replace this :

Code: Select all

ricevuto, x : string[1];

with this :

Code: Select all

ricevuto, x : string[2];

[hamradio]

Ok, may be that [1] is wrong, but why this happen with X variable and not with "Ricevuto".


EDIT: I follow your suggestion and change declaration from [1] to [2] but nothing change . The X variable stop the echos back to terminal agn.

Tnx Carlo IW2FIV

[janni]

I don't see you using the 'x' string anywhere, apart for the assignment, so the program behaviour is indeed strange.

I don' think you'll get any answer, though, as v 8.1 is obsolete (though official). There is v8.3 beta available with most quirks and bugs of v 8.1 fixed. You could try if the problem persists there.

BTW, there shouldn't be any reason prohibiting use of one character long strings (other than memory waste).