Compiler Operation
Invoking Pascal
Compilation Switches
File Input/Output
Special Functions and Procedures
Pascal/MT Symbolic Debugger
Pascal/MT Reserved Words
Notes
:Compiler Operation

     The Pascal/MT compiler exists in two versions,  each consisting of two 
8080  object  code files:  FLTCOMP.COM (renamed PASCAL.COM on ARIES-1)  and 
P2/FLT.OVL  for  the  version  in which REAL  numbers  are  implemented  as 
floating  point  values internally and BCDCOMP.COM and P2/BCD.OVL  for  the 
version  in  which REAL numbers are implemented as BCD  values  internally.  
These files are Pass 1 and Pass 2 of the Pascal/MT compiler,  respectively.  
Also required by the compiler are the following files --

          P1ERRORS.TXT   - Pass 1 Error Messages
          P2ERRORS.TXT   - Pass 2 Error Messages
          PASCAL/F.RTP   - Run-time Package (including debugger) for FLT
          PASCAL/B.RTP   - Run-time Package (including debugger) for BCD

     The  input  files to the Pascal/MT compiler must  have  the  extension 
'.SRC'  or '.PAS' indicating that it is a source program file.   There must 
be  a carriage return/line feed sequence at the end of each input line  and 
an input line may not be longer than 80 characters.
:Invoking Pascal

     The  Pascal/MT  compiler is invoked on ARIES-1 by using the  following 
command --

          PASCAL filename.DL

where  'filename'  is  the name of the file with the  extension  '.SRC'  or 
'.PAS' containing the Pascal/MT source statements to be compiled, D is Y or 
N  to indicate whether to include the debugger in the resultant .COM  file, 
and  L  is  Y or N to indicate whether to produce a  .PRN  file  (listing).  
PASCAL defaults to no debugger and no listing.  The four invocation options 
are --

          PASCAL filename     - no debugger, no listing
          PASCAL filename.Y   - debugger, no listing
          PASCAL filename.NY  - no debugger, listing
          PASCAL filename.YY  - debugger, listing

     For  usage  with the BCD version of the  compiler,  the  commands  are 
similar except that 'PASCAL' is replaced by 'BCDCOMP'.
:Compilation Switches
     Compile-time  options may be specified to the compiler from within the 
source file.   Such options take the form of special comments.  The form of 
these comments is
          (*$o info*) or {$o info}
where  'o'  is  the  letter of the option and  'info'  is  information 
particular to that option.  These options are --

          $I<filename>   Include <filename>.SRC into source stream
          $L+ or $L-     Turn listing on (default) or Turn listing off
          $P             Insert form feed into .PRN file
          $D+ or $D-     Turn debug code on (default) or Turn debug code off
          $C+            Use CALL instructions for real operations
          $Cn            Use RST n for real operations (n=0 ... 7)
          $O $aaaa       ORG program (run-time) at $aaaa (default 100H)
          $R $bbbb       ORG RAM data at $bbbb
          $Z $cc00       Set run-time size to $cc 256-byte pages
          $X $dddd       Set run-time stack space to $dddd (default $200)
          $S+ or $S-     Turn recursion or or Turn recursion off (default)
          $Q+ or $Q-     Enable verbose output (default) or Disable verbose
:File Input/Output
     The standard Pascal READ,  READLN,  WRITE, and WRITELN statements 
are  implemented for the CP/M console device.   WRITE or WRITELN to  a 
built-in  file called PRINTER is allowed to directly access  the  CP/M 
list device (like, WRITE(PRINTER,'Hello')).
     The following extensions are implemented to handle files --
          OPEN(fcbname,title,result{,extent_number});
               (extent_number defaults to 0)
          CLOSE(fcbname,result);
          CREATE(fcbname,title,result);
          DELETE(fcbname);
          BLOCKREAD(fcbname,buffer,result{,relativeblock});
          BLOCKWRITE(fcbname,buffer,result{,relativeblock});
where    fcbname : a variable of type TEXT (array 0..32 of CHAR)
         title   : ARRAY [0..11] of CHAR with
                    title[0]=disk   select  byte  (0=logged  in  disk, 
                      1=A,...)
                    title[1..8]=filename and title[9..11]=filetype
         result  : integer to contain returned value
         buffer  : ARRAY [0..127] of CHAR
         relativeblock : optional integer 0..255
:Special Functions and Procedures

     Pascal/MT supports the following special routines --

          PROC MOVE(source,dest,length-in-bytes);
          PROC EXIT;
          FUNC TSTBIT(16-bit-var,bit#):BOOLEAN;
          PROC SETBIT(VAR 16-bit-var,bit#);
          PROC CLRBIT(VAR 16-bit-var,bit#);
          FUNC SHR(16-bit-var,#bits):16-bit-result; {Shift Right}
          FUNC SHL(16-bit-var,#bits):16-bit-result; {Shift Left}
          FUNC LO(16-bit-var):16-bit-result;
          FUNC HI(16-bit-var):16-bit-result;
          FUNC SWAP(16-bit-var):16-bit-result;
          FUNC ADDR(variable reference):16-bit result;
          PROC WAIT(portnum:constant; mask:constant; polarity:boolean);
          FUNC SIZEOF(variable or type name):integer;
     Please refer to pp 32-33 of "Pascal/MT 3.0 Guide" for further info.
:Pascal/MT Symbolic Debugger

     The  debugging  facilities available to the user when  using  the 
debugger fall into two catagories -- program flow control and variable 
display.

     If  the user wishes to see the commands during the  execution  of 
the debugger, type a '?' followed by a return.

     The program flow commands provided in the symbolic debugger allow 
the user to debug the Pascal/MT program at the Pascal source statement 
level.   Included  are go/continue (with optional breakpoint),  trace, 
set/clear/display  permanent breakpoint and a mode which will  display 
the name of each procedure/function on the console as the procedure or 
function is entered.

     These commands are discussed briefly on the following displays --

Debugger Command:  G - Go with optional breakpoint

     Syntax:   G{,<linenumber>}
               G{,<proc/func name>}

     Go resumes execution where the program last stopped.   Breakpoint 
may be optionally set at a specific line or function/procedure.

Debugger Command:  T - Trace

     Syntax:   T{<integer>}

     Execute one or more lines of the program.

Debugger Command:  E - Procedure/Function Display Toggle

     Syntax:   {-}E

     E  engages display of the names of procedures/functions  entered;   
-E disengages it.

Debugger Command:  S - Set/Clear Slow Execution Mode

     Syntax:  {-}S

     S  allows  the user to select Fast,  Medium,  or  Slow  execution 
speed; -S causes the program to run at full speed.

Debugger Command:  P - Set/Clear Permanent Breakpoint

     Syntax:  -P     (* Clears breakpoint *)
              P<linenumber>
              P<proc/func name>

     P sets the permanent breakpoint; -P clears it.

Debugger Command:  B - Display Permanent Breakpoint

     Syntax:  B

     Displays line the permanent breakpoint is set for.

Debugger Command:  D - Variable Display

     Syntax:   D <global var>
               D <proc/func name>:<local var>
               D <func name>
               D <pointer name>^

     The D command is used as indicated.

Debugger Commands:  +,-,* - Variable Display

     Syntax:  *  -- display last value requested (using D or some other)
              +n -- display variable n bytes forward from last
              -n -- display variable n bytes backward from last
:Pascal/MT Reserved Words

     ABS            DO             LO             READ         TSTBIT
     ADDR           DOWNTO         MAXINT         READLN       TYPE
     AND            ELSE           MOD            REAL         UNTIL
     ARRAY          ENABLE         MOVE           RECORD       VAR
     BEGIN          END            NIL            REPEAT       WAIT
     BLOCKREAD      EXIT           NOT            RIM85        WHILE
     BLOCKWRITE     EXTERNAL       ODD            ROUND        WRITE
     BOOLEAN        FALSE          OF             SETBIT       WRITELN
     CASE           FILE           OPEN           SHL
     CHAIN          FOR            OR             SHR
     CHAR           FUNCTION       ORD            SIM85
     CHR            GOTO           OUTPUT         SIZEOF
     CLOSE          HI             PACKED         SQR
     CLRBIT         IF             PRED           SQRT
     CONST          INLINE         PRINTER        SUCC
     CREATE         INPUT          PROCEDURE      SWAP
     DELETE         INTEGER        PROGRAM        THEN
     DISABLE        INTERRUPT      RANDOMREAD     TO
     DIV            LABEL          RANDOMWRITE    TRUE
:Notes
     1. Hexadecimal values may be specified as $hhhh, like $1A = 1AH.
     2.  All  standard Pascal type definitions except ARRAY are  supported.  
The   standard   form   ARRAY...OF   ARRAY...    must   be   specified   as 
ARRAY[...,...,...], and a maximum of three dimensions may be used.
     3. Type TEXT is ARRAY [0..35] OF CHAR.
     4.  Interrupt Procedures,  declared as "PROCEDURE INTERRUPT[i] proc;", 
are supported, where i is the restart vector number (0..7).
     5.  CP/M  V2  random  file  access  is  supported  by  RANDOMREAD  and 
RANDOMWRITE.
     6.  Machine  code,  constant data,  and assembly language code may  be 
inserted using INLINE (see pp 37-39 of "Pascal/MT 3.0 User Guide").
     7. Chaining is supported by CHAIN, whose usage is "CHAIN(filename)".
     8. Redirected I/O is supported (see pp 42-43).

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