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).