Parseing PCL5

Delphi code:

function Buffer.PCLGet: boolean;
var
 Len: Word;
begin
{ Commented out?
 if PCLState > 2 then begin
 if PCLChrOne=PCLOldOne and PCLChrTwo=PCLOldTwo then begin
 Buffer.InsertP(Lower(PCLOldParm)
 Buffer.InsertS(ParmVal);
 PCLOldParm := PCLChrParm;
 end;
 else begin
 Buffer.InsertP(UpCase(PCLOldParm));
 Buffer.InsertP('#27'+PCLChrOne+PCLChrTwo
 PCLOldOne := PCLChrOne;
 PCLOldTwo := PCLChrTwo;
 Buffer.InsertS(ParmVal);
 PCLOldParm := PCLChrParm;
 end;
);
if PCLState in [1,3,4,5] and Data[0]=#27 then PCLState := 2;
if PCLState in [2,6,7] then begin
 ParmVal:='';
 if PCLState=2 then begin {starting a command, seen escape)
 PCLChrOne := Buffer.GetChar;
 if IsCharUpper(PCLChrOne) then
 PCLState := 3; (EOC on first character = 2 Char command)
 else begin
 PCLState := 6; {first term or 3 char command waiting}
 PCLChrOne := UpCase(PCLChrOne);
 ParmVal := Buffer.GetNum; {only sees a number on 3 char command)
 PCLChrTwo := Buffer.GetChar;
 if IsCharUpper(PCLChrTwo) then begin
 PCLChrParm := PCLChrTwo;
 PCLState := 4
 if Length(ParmVal)>O then begin
 PCLChrParm := UpCase(PCLChrTwo);
 end;
 end;
 end;
 if PCLState in [6,7] and Length(ParmVal) = O then begin (term waiting)
 ParmVal := Buffer.GetNum;
 PCLChrParm := Buffer.GetChar;
 if IsCharUpper(PCLChrParm) then
 PCLState := PCLState-2; {last term. 6 becomes 4, 7 becomes 5)
 else
 PCLChrParm := UpCase(PCLChrParm);
 end;
 if PCLState in [4,6,7] and PCLChrParm='W' then begin
 Len := ValS(ParmVal);
 Len := MinP(Len,EndPtr-BufPtr);
 Move(Binary, BufPtr[O], Len); Ilotta room for crashing here!)
 BufPtr := BufPtr+Len;
 PCLState := Min(PCLState +1,7); 14 becomes 5, 6 becomes 7~
 end;
 Buffer.Delete;
 PCLGet := True;
 end;
 else begin
 {We have ended a previous command and are being ask to load a PCL
 command but the escape character is not at the begining of the buffer
 indicating that something is wrong}
 PCLGet := False;
 end;
end;

Delphi PCLOut

procedure Buffer.PCLPut;
var
Ptr: PChar;
begin
 Ptr := BufPtr;
 case PCLState of
 1..3: begin
{
Previously:
 1 Not in PCL
or 2 Seen an Escape
or 3 Loaded a 2 char command
With any of these, this is the first term of the new command
}
 if PCLState o 2 then Buffer.InsertS(#27); {not already passed the escape}
 Buffer.InsertS(PCLChrOne));
 if IsCharLower(PCLChrOne) then begin
 Buffer.InsertS(LowerCase(PCLChrTwo));
 Buffer.InsertS(ParmVal);
 Buffer.StuffS(UpCase(PCLChrParm));
 end;
 end;
 4..5: begin
{
or 4 Loaded last term of command
or 5 Loaded last term with binary data
}
 end;
 6..7: begin
{
Previously:
6 Loaded a term, another term waiting
or 7 Loaded a term with binary data, another term waiting
}
 end;
 end;

QBASIC

true = -1
false = 0
DataBinary = 0
DataText = 1
DataPCL = 2
DataUnknown = 3
DataMode = DataText
PCLStart = 0
PCLCmd = 1
PCLGrp = 2
PCLVal = 3
PCLPrm = 4
PCLUnknown = 5
PCLState = PCLUnknown
TYPE TextFile
 Chars AS STRING * 1
DIM MyFile AS TextFile
OPEN $ FOR RANDOM AS #1 LEN = LEN(MyFile)
inlen = LOF(1)
WHILE incount <= inlen
 incount = incount + 1
 GET #1, incount, MyFile
 in = ASC(MyFile.Chars)
 IF DataMode = DataPCL THEN
 PRINT #2, "CHAR '"; CHR$(in); "'";
 IF PCLState = PCLVal THEN
 SELECT CASE in
 CASE 43 'positive
 PCLSign = 1
 PRINT #2, "+"
 CASE 45 'negative
 PCLSign = -1
 PRINT #2, "-"
 CASE 46 'decimal
 PCLFrac = true
 PRINT #2, "."
 
 CASE 48 TO 57 'digit
 
 IF PCLFrac THEN
 PCLValueFrac = PCLValueFrac * 10
 PRINT #2, PCLValueFrac
 END IF
 PCLValue = PCLValue * 10 + (in - 48)
 PRINT #2, PCLValue
 
 CASE ELSE
 PCLPrms = PCLPrms + 1
 PCLValue(PCLPrms) = PCLValue * PCLSign
 PCLValueFrac(PCLPrms) = PCLValueFrac
 PCLValue = 0
 PCLSign = 1
 PCLFrac = false
 PCLValueFrac = 1
 PCLParm(PCLPrms) = ASC(UCASE$(MyFile.Chars)) - 64
 PRINT #2, " parm #"; PCLPrms
 END SELECT
 
 END IF
 IF PCLState = PCLGrp THEN
 PCLGroup = INSTR("abcdflprstuv", MyFile.Chars)
 PCLGr$ = MyFile.Chars
 PRINT #2, " group"
 PCLState = PCLVal
 END IF
 
 IF PCLState = PCLCmd THEN
 i = INSTR("=9EYZ", MyFile.Chars)
 IF i > 0 THEN
 PCLCommand = ASC(MID$(",-./+", i, 1)) - 32
 PRINT #2, " two-char"
 DataMode = DataUnknown
 PCLState = PCLUnknown
 ELSE
 PCLCommand = in - 32
 PCLState = PCLGrp
 PRINT #2, " parm-command"
 END IF
 
 END IF
 
 
 IF in > 64 AND in < 96 THEN 'Termination Character
 IF in = 87 THEN '=W so it is binary data
 DataMode = DataBinary
 BinaryLength = PCLValue(1)
 PCLState = PCLUnknown
 ELSE
 DataMode = DataUnknown 'we dont know what is next so mode is undefined
 PCLState = PCLUnknown
 END IF
 END IF
 
 GOTO nextchar
 END IF
 
 IF in = 27 AND DataMode <> DataBinary THEN
 DataMode = DataPCL
 PCLState = PCLCmd
 PCLPrms = 0
 PRINT #2, "pcl "
' bitcount = bitcount + 4
 GOTO nextchar
 END IF

See:

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