As we said a digit can be translated into a byte like this :
X,a5,a6,a1,a4,a3,a7,a2 [X we ignore it. It is the negative sign or the point]
Notice that the $X in pascal are values in hex
{
The order of the segments is defined like this :
We define digit like this : X,a5,a6,a1,a4,a3,a7,a2 [X we ignore it is negative sign or the point]
////s1////
// //
s6 s2
// //
////s7////
// //
s5 s3
// //
////s4////
}
function TFormMain.SevenSegmentsToChar(digit:byte) : char;
begin
if digit=$0 then result := ' ' //00000000->' '
else if digit=$5 then result := '1' //00000101->'1'
else if digit=$5B then result := '2' //01011011->'2'
else if digit=$1F then result := '3' //00011111->'3'
else if digit=$27 then result := '4' //00100111->'4'
else if digit=$3E then result := '5' //00111110->'5'
else if digit=$7E then result := '6' //01111110->'6'
else if digit=$15 then result := '7' //00010101->'7'
else if digit=$7F then result := '8' //01111111->'8'
else if digit=$3F then result := '9' //00111111->'9'
else if digit=$7D then result := '0' //01111101->'0'
else if digit=$68 then result := 'L' //01101000->'L'
else if digit=$60 then result := 'I' //01100000->'I'
else if digit=$4E then result := 'o' //01001110->'o'
else if digit=$72 then result := 'F' //01110010->'F'
else if digit=$7A then result := 'E' //01111010->'E'
else result := 'X';
end;
With the help of the masking technique (bitwise AND) the parsing function looks like this :
procedure TFormMain.ParseStatus();
var res : integer;
digit : byte; // we define digit like this : X,a5,a6,a1,a4,a3,a7,a2 [X we ignore it is negative sign or the point]
y:double;
begin
//FIRST SEGMENT
//Parse the IsRS232
res := My_Multimeter.Code.Value[0] and $1; //bitwise operation : masking technique XXXXXXXX AND 00000001 give as 0000000X
if res = $1 then
My_Multimeter.Status.IsRS232:=true
else
My_Multimeter.Status.IsRS232:=false;
//Parse the IsAuto
res := My_Multimeter.Code.Value[0] and $2; //bitwise operation : masking technique XXXXXXXX AND 00000010 give as 000000X0
if res = $2 then //10 in binary
My_Multimeter.Status.IsAuto:=true
else
My_Multimeter.Status.IsAuto:=false;
//Parse the AC_DC_None
res := My_Multimeter.Code.Value[0] and $4; //bitwise operation : masking technique XXXXXXXX AND 00000100 give as 00000X00
if res = $4 then begin // 100 in binary
My_Multimeter.Status.AC_DC_None:=DC;
end else begin //is not DC let's see if it is AC else is NONE
res := My_Multimeter.Code.Value[0] and $8; //bitwise operation : masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.AC_DC_None:=AC
else
My_Multimeter.Status.AC_DC_None:=None;
end;
//////////////////////////////////////////////////////////////////////////////
//SECOND+THIRD SEGMENT
//Parse negative sign
res := My_Multimeter.Code.Value[1] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.ValuePrefix:='-'
else
My_Multimeter.Status.ValuePrefix:='';
//Parse the first digit
res := My_Multimeter.Code.Value[1] and $7; // XXXXXXXX AND 00000111 give as 00000XXX
digit := res shl 4; //00000XXX -> 0XXX0000
res := My_Multimeter.Code.Value[2] and $F; // YYYYYYYY AND 00001111 give as 0000YYYY
digit := digit + res; //0XXX0000 + 0000YYYY -> 0XXXYYYY
My_Multimeter.Status.ValuePrefix += SevenSegmentsToChar(digit);
//////////////////////////////////////////////////////////////////////////////
//forth+fifth SEGMENT
//Parse the .
res := My_Multimeter.Code.Value[3] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.ValuePrefix+='.'
else
My_Multimeter.Status.ValuePrefix+='';
//Parse the second digit
res := My_Multimeter.Code.Value[3] and $7; // XXXXXXXX AND 00000111 give as 00000XXX
digit := res shl 4; //00000XXX -> 0XXX0000
res := My_Multimeter.Code.Value[4] and $F; // YYYYYYYY AND 00001111 give as 0000YYYY
digit := digit + res; //0XXX0000 + 0000YYYY -> 0XXXYYYY
My_Multimeter.Status.ValuePrefix += SevenSegmentsToChar(digit);
//////////////////////////////////////////////////////////////////////////////
//sixth+seventh SEGMENT
//Parse the .
res := My_Multimeter.Code.Value[5] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.ValuePrefix+='.'
else
My_Multimeter.Status.ValuePrefix+='';
//Parse the third digit
res := My_Multimeter.Code.Value[5] and $7; // XXXXXXXX AND 00000111 give as 00000XXX
digit := res shl 4; //00000XXX -> 0XXX0000
res := My_Multimeter.Code.Value[6] and $F; // YYYYYYYY AND 00001111 give as 0000YYYY
digit := digit + res; //0XXX0000 + 0000YYYY -> 0XXXYYYY
My_Multimeter.Status.ValuePrefix += SevenSegmentsToChar(digit);
//////////////////////////////////////////////////////////////////////////////
//eight+ninth SEGMENT
//Parse the .
res := My_Multimeter.Code.Value[7] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.ValuePrefix+='.'
else
My_Multimeter.Status.ValuePrefix+='';
//Parse the forth digit
res := My_Multimeter.Code.Value[7] and $7; // XXXXXXXX AND 00000111 give as 00000XXX
digit := res shl 4; //00000XXX -> 0XXX0000
res := My_Multimeter.Code.Value[8] and $F; // YYYYYYYY AND 00001111 give as 0000YYYY
digit := digit + res; //0XXX0000 + 0000YYYY -> 0XXXYYYY
My_Multimeter.Status.ValuePrefix += SevenSegmentsToChar(digit);
//10-13 segment
//Parse the IsDiode
res := My_Multimeter.Code.Value[9] and $1; //bitwise operation : masking technique XXXXXXXX AND 00000001 give as 0000000X
if res = $1 then
My_Multimeter.Status.IsDiode:=true
else
My_Multimeter.Status.IsDiode:=false;
//Parse the IsSound
res := My_Multimeter.Code.Value[10] and $1; //bitwise operation : masking technique XXXXXXXX AND 00000001 give as 0000000X
if res = $1 then
My_Multimeter.Status.IsSound:=true
else
My_Multimeter.Status.IsSound:=false;
//Parse the IsHold
res := My_Multimeter.Code.Value[11] and $1; //bitwise operation : masking technique XXXXXXXX AND 00000001 give as 0000000X
if res = $1 then
My_Multimeter.Status.IsHold:=true
else
My_Multimeter.Status.IsHold:=false;
//Parse the IsRelative
res := My_Multimeter.Code.Value[11] and $2; //bitwise operation : masking technique XXXXXXXX AND 00000010 give as 000000X0
if res = $2 then //10 in binary
My_Multimeter.Status.IsRelative:=true
else
My_Multimeter.Status.IsRelative:=false;
//Parse the IsBattery
res := My_Multimeter.Code.Value[12] and $1; //bitwise operation : masking technique XXXXXXXX AND 00000001 give as 0000000X
if res = $1 then
My_Multimeter.Status.IsBattery:=true
else
My_Multimeter.Status.IsBattery:=false;
//Parse the unit prefix K/M/n/u/m (Kilo-,Mega-,nano-,micro-,milli-)
My_Multimeter.Status.UnitPrefix:='';
if ComboBoxUnitValue.Text = 'x10Lux' then begin
My_Multimeter.Status.UnitPrefix:='x10';
end else if ComboBoxUnitValue.Text = 'AUTO' then begin
//Parse the Kilo
res := My_Multimeter.Code.Value[9] and $2; //bitwise operation : masking technique XXXXXXXX AND 00000010 give as 000000X0
if res = $2 then //10 in binary
My_Multimeter.Status.UnitPrefix:='K';
//Parse the Mega
res := My_Multimeter.Code.Value[10] and $2; //bitwise operation : masking technique XXXXXXXX AND 00000010 give as 000000X0
if res = $2 then //10 in binary
My_Multimeter.Status.UnitPrefix:='M';
//Parse the nano
res := My_Multimeter.Code.Value[9] and $4; //bitwise operation : masking technique XXXXXXXX AND 00000100 give as 00000X00
if res = $4 then // 100 in binary
My_Multimeter.Status.UnitPrefix:='n';
//Parse the micro
res := My_Multimeter.Code.Value[9] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.UnitPrefix:='u';
//Parse the milli
res := My_Multimeter.Code.Value[10] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.UnitPrefix:='m';
end;
//Parse unitvalue Ohm Hz V A F %
if ComboBoxUnitValue.Text = 'AUTO' then begin
//Inizialize....
My_Multimeter.Status.UnitValue:='';
//Parse the Hz
res := My_Multimeter.Code.Value[12] and $2; //bitwise operation : masking technique XXXXXXXX AND 00000010 give as 000000X0
if res = $2 then //10 in binary
My_Multimeter.Status.UnitValue:='Hz';
//Parse the %
res := My_Multimeter.Code.Value[10] and $4; //bitwise operation : masking technique XXXXXXXX AND 00000100 give as 00000X00
if res = $4 then // 100 in binary
My_Multimeter.Status.UnitValue:='%';
//Parse the Ohm
res := My_Multimeter.Code.Value[11] and $4; //bitwise operation : masking technique XXXXXXXX AND 00000100 give as 00000X00
if res = $4 then // 100 in binary
My_Multimeter.Status.UnitValue:='Ohm';
//Parse the Volt
res := My_Multimeter.Code.Value[12] and $4; //bitwise operation : masking technique XXXXXXXX AND 00000100 give as 00000X00
if res = $4 then // 100 in binary
My_Multimeter.Status.UnitValue:='V';
//Parse the Farad
res := My_Multimeter.Code.Value[11] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.UnitValue:='F';
//Parse the Ampere
res := My_Multimeter.Code.Value[12] and $8; // masking technique XXXXXXXX AND 00001000 give as 0000X000
if res = $8 then // 1000 in binary
My_Multimeter.Status.UnitValue:='A';
end else begin //The unitvalue does not included in the code so i have to put it manually
My_Multimeter.Status.UnitValue:=ComboBoxUnitValue.Text;
end;
//calulate value without prefix
if TryStrToFloat(My_Multimeter.Status.ValuePrefix, y) then begin
My_Multimeter.Status.ValueNoPrefix:=floattostr(y);
if My_Multimeter.Status.UnitPrefix = 'K' then
My_Multimeter.Status.ValueNoPrefix:=floattostr(y*1000)
else if My_Multimeter.Status.UnitPrefix = 'M' then
My_Multimeter.Status.ValueNoPrefix:=floattostr(y*1000000)
else if My_Multimeter.Status.UnitPrefix = 'm' then
My_Multimeter.Status.ValueNoPrefix:=floattostr(y*0.001)
else if My_Multimeter.Status.UnitPrefix = 'u' then
My_Multimeter.Status.ValueNoPrefix:=floattostr(y*0.000001)
else if My_Multimeter.Status.UnitPrefix = 'n' then
My_Multimeter.Status.ValueNoPrefix:=floattostr(y*0.000000001);
end else
My_Multimeter.Status.ValueNoPrefix:='0';
end;
That's all for now.
We have seen in this article how we defined our data structure from the documentation and how we can "understand the code" and fill the Multimeter status with the captured code information.
In the next article we will see the synaser integration library and the plotting library in order to obtain our final software.
Stay tuned as always !