From 6c2f866b01ac2472f1a0dbffbaf103678c082f39 Mon Sep 17 00:00:00 2001
From: CrazyEttin <>
Date: Sun, 21 Aug 2022 10:27:02 +0300
Subject: [PATCH] Enforce the emulated terminal being dumb, rename settape to
 tape, and reword the readme slightly

---
 emulator.pas            | 21 ++++++++++++++++++---
 readme.md               |  8 ++++----
 settape.pas => tape.pas | 12 ++++++------
 3 files changed, 28 insertions(+), 13 deletions(-)
 rename settape.pas => tape.pas (87%)

diff --git a/emulator.pas b/emulator.pas
index 6d09976..f226b4e 100644
--- a/emulator.pas
+++ b/emulator.pas
@@ -31,6 +31,22 @@ var
     {$endif}
     Ch, Scan: ansichar; //Character for input and output and scancode for non-ASCII keys
 
+//Terminal output
+procedure Output;
+begin
+    //Do not output most of the control codes
+    if Ch <= ansichar ($1f) then begin
+        if Ch = ansichar (7) then write (Ch) //Bell
+        else if Ch = ansichar (8) then write (Ch) //Backspace
+        else if Ch = ansichar ($a) then write (Ch) //Line feed
+        else if Ch = ansichar ($d) then write (Ch) //Carriage return
+        else write (''); //Others
+    end
+    else if Ch = ansichar ($7f) then write ('') //Delete
+    //Output all regular characters
+    else write (Ch);
+end;
+
 begin
 
     //Initialise the halt flag and the pointers
@@ -187,7 +203,7 @@ begin
                     end;
                 end;
                 //Process the keypress
-                write (Ch); //Local echo
+                Output; //Local echo
                 R [X] := byte (Ch);
             end
             //Tape reader
@@ -225,7 +241,6 @@ begin
                     except
                     end;
                 end;
-
             end
             {$endif}
             //Regular load
@@ -236,7 +251,7 @@ begin
             //Terminal output
             if Addr = IO then begin
                 Ch := ansichar (R [X]);
-                write (Ch);
+                Output;
             end
             //Printer
             {$ifdef printer}
diff --git a/readme.md b/readme.md
index 6b16992..d6811bc 100644
--- a/readme.md
+++ b/readme.md
@@ -87,7 +87,7 @@ Memory-Mapped Devices
 ---------------------
 
 Input (when read from) and output (when written to) are mapped to
-address FFFF. The emulator emulates a dumb terminal with local echo.
+address FFFF. The emulator emulates a glass teletype with local echo.
 
 Arbitrary devices can be mapped to the other reserved addresses.
 
@@ -96,13 +96,13 @@ and an emulated punched tape reader and punch with the arguments
 -dprinter and -dtape respectively. The printer is mapped to address FFFE
 and the tape reader and punch to FFFD. The printer prints into
 /dev/usb/lp0 and the tape files read from and punched to are (re)set
-using the settape program. If you wish to use a different setup you have
-to modify the code yourself.
+using the program tape. If you wish to use a different setup you have to
+modify the code yourself.
 
 Initial Program Loader
 ----------------------
 
 At boot the initial program loader loads a program to the memory
 starting from address 0 after which is cedes control to the CPU. The
-emulator loads the program from a file.
+emulator loads the program from a ROM file.
 
\ No newline at end of file
diff --git a/settape.pas b/tape.pas
similarity index 87%
rename from settape.pas
rename to tape.pas
index 9e06228..db9beca 100644
--- a/settape.pas
+++ b/tape.pas
@@ -1,4 +1,4 @@
-program Settape;
+program Tape;
 
 {$MODE OBJFPC}
 
@@ -6,22 +6,22 @@ uses SysUtils;
 
 type
     //Tape file path and reset state
-    Tape = record
+    TapeState = record
         Path: shortstring;
         Reset: boolean;
         Pos: integer;
     end;
 
 var
-    Reader, Punch: Tape; //States of the reader and punch
-    State: file of Tape; //File storing the states of the reader and punch
+    Reader, Punch: TapeState; //States of the reader and punch
+    State: file of TapeState; //File storing the states of the reader and punch
     DoRead, DoPunch: boolean; //Whether to reset the reader or the punch
 
 begin
 
     //Check whether to set the reader, the punch, or both
     if ParamCount <> 1 then begin
-        writeln ('Usage: settape reader/punch/both');
+        writeln ('Usage: tape reader/punch/both');
         halt;
     end;
     if ParamStr (1) = 'reader' then begin
@@ -37,7 +37,7 @@ begin
         DoPunch := true;
     end
     else begin
-        writeln ('Usage: settape reader/punch/both');
+        writeln ('Usage: tape reader/punch/both');
         halt;
     end;