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{
TERRY GRANT
Here is a Unit I posted some time ago For use With EMSI Sessions. Hope it
helps some of you out. You will require a fossil or Async Interface for
this to compile!
}
Program Emsi;
Uses
Dos , Crt, Fossil;
Type
HexString = String[4];
Const
FingerPrint = '{EMSI}';
System_Address = '1:210/20.0'; { Your address }
PassWord = 'PASSWord'; { Session passWord }
Link_Codes = '{8N1}'; { Modem setup }
Compatibility_Codes = '{JAN}'; { Janis }
Mailer_Product_Code = '{00}';
Mailer_Name = 'MagicMail';
Mailer_Version = '1.00';
Mailer_Serial_Number = '{Alpha}';
EMSI_INQ : String = '**EMSI_INQC816';
EMSI_REQ : String = '**EMSI_REQA77E';
EMSI_ACK : String = '**EMSI_ACKA490';
EMSI_NAK : String = '**EMSI_NAKEEC3';
EMSI_CLI : String = '**EMSI_CLIFA8C';
EMSI_ICI : String = '**EMSI_ICI2D73';
EMSI_HBT : String = '**EMSI_HBTEAEE';
EMSI_IRQ : String = '**EMSI_IRQ8E08';
Var
EMSI_DAT : String; { NOTE : EMSI_DAT has no maximum length }
Length_EMSI_DAT : HexString; { Expressed in Hexidecimal }
Packet : String;
Rec_EMSI_DAT : String; { EMSI_DAT sent by the answering system }
Len_Rec_EMSI_DAT : Word;
Len,
CRC : HexString;
R : Registers;
C : Char;
Loop,ComPort,TimeOut,Tries : Byte;
Temp : String;
Function Up_Case(St : String) : String;
begin
For Loop := 1 to Length(St) do
St[Loop] := Upcase(St[Loop]);
Up_Case := St;
end;
Function Hex(i : Word) : HexString;
Const
hc : Array[0..15] of Char = '0123456789ABCDEF';
Var
l, h : Byte;
begin
l := Lo(i);
h := Hi(i);
Hex[0] := #4; { Length of String = 4 }
Hex[1] := hc[h shr 4];
Hex[2] := hc[h and $F];
Hex[3] := hc[l shr 4];
Hex[4] := hc[l and $F];
end {Hex} ;
Function Power(Base,E : Byte) : LongInt;
begin
Power := Round(Exp(E * Ln(Base) ));
end;
Function Hex2Dec(HexStr : String) : LongInt;
Var
I,HexBit : Byte;
Temp : LongInt;
Code : Integer;
begin
Temp := 0;
For I := Length(HexStr) downto 1 do
begin
If HexStr[I] in ['A','a','B','b','C','c','D','d','E','e','F','f'] then
Val('$' + HexStr[I],HexBit,Code)
else
Val(HexStr[I],HexBit,Code);
Temp := Temp + HexBit * Power(16,Length(HexStr) - I);
end;
Hex2Dec := Temp;
end;
Function Bin2Dec(BinStr : String) : LongInt;
{ Maximum is 16 bits, though a requirement For more would be }
{ easy to accomodate. Leading zeroes are not required. There }
{ is no error handling - any non-'1's are taken as being zero. }
Var
I : Byte;
Temp : LongInt;
BinArray : Array[0..15] of Char;
begin
For I := 0 to 15 do
BinArray[I] := '0';
For I := 0 to Pred(Length(BinStr)) do
BinArray[I] := BinStr[Length(BinStr) - I];
Temp := 0;
For I := 0 to 15 do
If BinArray[I] = '1' then
inc(Temp,Round(Exp(I * Ln(2))));
Bin2Dec := Temp;
end;
Function CRC16(s:String):Word; { By Kevin Cooney }
Var
crc : LongInt;
t,r : Byte;
begin
crc:=0;
For t:=1 to length(s) do
begin
crc:=(crc xor (ord(s[t]) shl 8));
For r:=1 to 8 do
if (crc and $8000)>0 then
crc:=((crc shl 1) xor $1021)
else
crc:=(crc shl 1);
end;
CRC16:=(crc and $FFFF);
end;
{**** FOSSIL Routines ****}
{**** Removed from Code ***}
Procedure Hangup;
begin
Write2Port('+++'+#13);
end;
{**** EMSI Handshake Routines ****}
Procedure Create_EMSI_DAT;
begin
FillChar(EMSI_DAT,255,' ');
EMSI_DAT := FingerPrint + '{' + System_Address + '}{'+ PassWord + '}' +
Link_Codes + Compatibility_Codes + Mailer_Product_Code +
'{' + Mailer_Name + '}{' + Mailer_Version + '}' +
Mailer_Serial_Number;
Length_EMSI_DAT := Hex(Length(EMSI_DAT));
end;
Function Carrier_Detected : Boolean;
begin
TimeOut := 20; { Wait approximately 20 seconds }
Repeat
Delay(1000);
Dec(TimeOut);
Until (TimeOut = 0) or (Lo(StatusReq) and $80 = $80);
If Timeout = 0 then
Carrier_Detected := False
else
Carrier_Detected := True;
end;
Function Get_EMSI_REQ : Boolean;
begin
Temp := '';
Purge_Input;
Repeat
C := ReadKeyfromPort;
If (C <> #10) and (C <> #13) then
Temp := Temp + C;
Until Length(Temp) = Length(EMSI_REQ);
If Up_Case(Temp) = EMSI_REQ then
get_EMSI_REQ := True
else
get_EMSI_REQ := False;
end;
Procedure Send_EMSI_DAT;
begin
CRC := Hex(CRC16('EMSI_DAT' + Length_EMSI_DAT + EMSI_DAT));
Write2Port('**EMSI_DAT' + Length_EMSI_DAT + EMSI_DAT + CRC);
end;
Function Get_EMSI_ACK : Boolean;
begin
Temp := '';
Repeat
C := ReadKeyfromPort;
If (C <> #10) and (C <> #13) then
Temp := Temp + C;
Until Length(Temp) = Length(EMSI_ACK);
If Up_Case(Temp) = EMSI_ACK then
get_EMSI_ACK := True
else
get_EMSI_ACK := False;
end;
Procedure Get_EMSI_DAT;
begin
Temp := '';
For Loop := 1 to 10 do { Read in '**EMSI_DAT' }
Temp := Temp + ReadKeyfromPort;
Delete(Temp,1,2); { Remove the '**' }
Len := '';
For Loop := 1 to 4 do { Read in the length }
Len := Len + ReadKeyFromPort;
Temp := Temp + Len;
Len_Rec_EMSI_DAT := Hex2Dec(Len);
Packet := '';
For Loop := 1 to Len_Rec_EMSI_DAT do { Read in the packet }
Packet := Packet + ReadKeyfromPort;
Temp := Temp + Packet;
CRC := '';
For Loop := 1 to 4 do { Read in the CRC }
CRC := CRC + ReadKeyFromPort;
Rec_EMSI_DAT := Packet;
Writeln('Rec_EMSI_DAT = ',Rec_EMSI_DAT);
If Hex(CRC16(Temp)) <> CRC then
Writeln('The recieved EMSI_DAT is corrupt!!!!');
end;
begin
{ Assumes connection has been made at this point }
Tries := 0;
Repeat
Write2Port(EMSI_INQ);
Delay(1000);
Inc(Tries);
Until (Get_EMSI_REQ = True) or (Tries = 5);
If Tries = 5 then
begin
Writeln('Host system failed to acknowledge the inquiry sequence.');
Hangup;
Halt;
end;
{ Used For debugging }
Writeln('Boss has acknowledged receipt of EMSI_INQ');
Send_EMSI_DAT;
Tries := 0;
Repeat
Inc(Tries);
Until (Get_EMSI_ACK = True) or (Tries = 5);
If Tries = 5 then
begin
Writeln('Host system failed to acknowledge the EMSI_DAT packet.');
Hangup;
halt;
end;
Writeln('Boss has acknowledged receipt of EMSI_DAT');
Get_EMSI_DAT;
Write2Port(EMSI_ACK);
{ Normally the File transfers would start at this point }
Hangup;
end.
{
This DOES not include all the possibilities in an EMSI Session.
}
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