From 2b92cf26a5b1d96c8596c1c7dfe2c13894b69259 Mon Sep 17 00:00:00 2001
From: CrazyEttin <>
Date: Mon, 15 Aug 2022 17:21:01 +0300
Subject: [PATCH] Add support for non-ASCII keys and better the punched tape
 support

---
 emulator.pas | 48 ++++++++++++++++++++++++++++++++++++------------
 readme.md    | 16 ++++++++--------
 2 files changed, 44 insertions(+), 20 deletions(-)

diff --git a/emulator.pas b/emulator.pas
index 0b71b42..15454ad 100644
--- a/emulator.pas
+++ b/emulator.pas
@@ -8,7 +8,7 @@ const
     IO = $ffff;
 
 var
-    Hlt: boolean; //Halt flag
+    Hlt, ASCII: boolean; //Halt and ASCII flags
     Op: 0 .. $f; //Opcode
     X, Y: 0 .. 3; //Register arguments
     Addr, IP, RP: word; //Address argument and instruction and return pointers
@@ -16,9 +16,10 @@ var
     Mem: array [0 .. $ffef] of byte; //Memory
     Prog{$ifdef printer}, Prn{$endif}{$ifdef tape}, TapeIn, TapeOut{$endif}: file of byte; //Program file, line printer, and punched tape reader and punch
     {$ifdef tape}
-    TapePos: integer; //Punched tape reader position pointer
+    TapeInFile: string; //Punched tape reader source file
+    TapeInPos: integer; //Punched tape reader position pointer
     {$endif}
-    Ch: ansichar; //Character for input and output
+    Ch, Scan: ansichar; //Character for input and output and scancode for non-ASCII keys
 
 begin
 
@@ -27,7 +28,8 @@ begin
     IP := 0;
     RP := $fff0;
     {$ifdef tape}
-    TapePos := 0;
+    TapeInFile := ' ';
+    TapeInPos := 0;
     {$endif}
 
     //Read a program file and check for errors
@@ -129,26 +131,48 @@ begin
         else if Op = $a then begin
             //Terminal input
             if Addr = IO then begin
+                //Read a keypress
+                repeat
                 Ch := ReadKey;
+                    //Check for non-ASCII keys
+                    if Ch = ansichar (0) then begin
+                        //Non-ASCII
+                        if keypressed then begin
+                            Scan := ReadKey;
+                            {$ifdef tape}
+                            //Insert a tape in the tape reader
+                            if Scan = ansichar ($52) then begin
+                                writeln ();
+                                write ('Tape to be read: ');
+                                readln (TapeInFile);
+                                if TapeInFile = '' then TapeInFile := ' ';
+                                TapeInPos := 0
+                            end;
+                            {$endif}
+                            ASCII := false;
+                        end
+                        //Null
+                        else ASCII := true;
+                    end
+                    //Other ASCII
+                    else ASCII := true;
+                until ASCII = true;
+                //Process the keypress
                 write (Ch); //Local echo
                 R [X] := byte (Ch);
             end
             //Tape reader
             {$ifdef tape}
             else if Addr = $fffd then begin
-                assign (TapeIn, 'tapein');
+                assign (TapeIn, TapeInFile);
                 try
                     reset (TapeIn);
-                    seek (TapeIn, TapePos);
-                    if eof (TapeIn) = false then begin
-                        read (TapeIn, R [X]);
-                        TapePos := TapePos + 1;
-                    end
-                    else R [X] := 0;
+                    seek (TapeIn, TapeInPos);
+                    read (TapeIn, R [X]);
+                    TapeInPos := TapeInPos + 1;
                     close (TapeIn);
                 except
                     R [X] := 0;
-                    TapePos := 0;
                 end;
             end
             {$endif}
diff --git a/readme.md b/readme.md
index 2a04ceb..78d9f05 100644
--- a/readme.md
+++ b/readme.md
@@ -91,14 +91,14 @@ this.
 
 Arbitrary devices can be mapped to the other reserved addresses.
 
-The emulator can be compiled with support for a line printer at
-/dev/usb/lp0 with the argument -dprinter, and for an emulated punched
-tape reader and punch at tapein and tapeout respectively with -dtape.
-The printer is mapped to address FFFE in the emulator and the tape
-reader and punch to FFFD. To reset the tape reader to the beginning of a
-tape, for example to change the tape, read once with no file at tapein.
-If you wish to use a different setup you have to modify the code
-yourself.
+The emulator can be compiled with support for a line printer and an
+emulated punched tape reader and punch with the arguments -dprinter and
+-dtape respectively. The printer outputs into /dev/usb/lp0 and the tape
+punch to tapeout. To (re)set the tape to be read press the insert key at
+any input and enter a file name; the input will resume after this. The
+printer is mapped to address FFFE in the emulator and the tape reader
+and punch to FFFD. If you wish to use a different setup you have to
+modify the code yourself.
 
 Initial Program Loader
 ----------------------