diff --git a/src/library/s3/ethBase64.Mod b/src/library/s3/ethBase64.Mod
new file mode 100644
index 00000000..66bcde05
--- /dev/null
+++ b/src/library/s3/ethBase64.Mod
@@ -0,0 +1,233 @@
+MODULE ethBase64;  (* Adapted for VOC from Oberon System 3 *)
+IMPORT Files, Texts, Oberon, Out;
+
+VAR
+  encTable: ARRAY 64 OF CHAR;
+  decTable: ARRAY 128 OF INTEGER;
+  W: Texts.Writer;
+
+PROCEDURE DecodeText*(T: Texts.Text; beg: LONGINT; F: Files.File): BOOLEAN;
+VAR
+  R: Texts.Reader;
+  codes: ARRAY 4 OF INTEGER;
+  Ri: Files.Rider;
+  i: INTEGER;
+  ch: CHAR;
+  ok, end: BOOLEAN;
+BEGIN
+  Files.Set(Ri, F, 0);
+  ok := TRUE; end := FALSE;
+  Texts.OpenReader(R, T, beg);
+  Texts.Read(R, ch);
+  REPEAT
+    i := 0;
+    WHILE ~R.eot & ok & (i < 4) DO
+      WHILE ~R.eot & (ch <= " ") DO
+        Texts.Read(R, ch)
+      END;
+      IF (ch >= 0X) & (ch < 80X) THEN
+        codes[i] := decTable[ORD(ch)];
+        ok := codes[i] >= 0; INC(i);
+        IF ok THEN
+          Texts.Read(R, ch)
+        END
+      ELSE
+        ok := FALSE
+      END
+    END;
+    IF i > 0 THEN
+      IF ok & (i = 4) THEN
+        Files.Write(Ri, CHR(ASH(codes[0], 2)+ASH(codes[1], -4)));
+        Files.Write(Ri, CHR(ASH(codes[1], 4)+ASH(codes[2], -2)));
+        Files.Write(Ri, CHR(ASH(codes[2], 6)+codes[3]))
+      ELSIF ch = "=" THEN
+        ok := TRUE; end := TRUE; DEC(i);
+        IF i = 2 THEN
+          Files.Write(Ri, CHR(ASH(codes[0], 2)+ASH(codes[1], -4)))
+        ELSIF i = 3 THEN
+          Files.Write(Ri, CHR(ASH(codes[0], 2)+ASH(codes[1], -4)));
+          Files.Write(Ri, CHR(ASH(codes[1], 4)+ASH(codes[2], -2)))
+        ELSIF i # 0 THEN
+          ok := FALSE
+        END
+      ELSE
+        end := TRUE
+      END
+    ELSE
+      end := TRUE
+    END
+  UNTIL R.eot OR end;
+  RETURN ok
+END DecodeText;
+
+PROCEDURE Decode*;
+VAR
+  S: Texts.Scanner;
+  F: Files.File;
+  T: Texts.Text;
+  beg, end, time: LONGINT;
+  res: INTEGER;
+BEGIN
+  Texts.OpenScanner(S, Oberon.Par.text, Oberon.Par.pos);
+  Texts.Scan(S);
+  IF S.class IN {Texts.Name, Texts.String} THEN
+    Texts.WriteString(W, S.s);
+    F := Files.New(S.s);
+    Texts.Scan(S);
+    IF (S.class = Texts.Char) & ((S.c = "@") OR (S.c = "^")) THEN
+      T := NIL;
+      time := -1;
+      Oberon.GetSelection(T, beg, end, time);
+      IF T = NIL THEN
+        Texts.WriteString(W, " - no selection");
+        Texts.WriteLn(W);
+        Texts.Append(Oberon.Log, W.buf);
+        RETURN
+      END
+    ELSIF S.class IN {Texts.Name, Texts.String} THEN
+      NEW(T);
+      Texts.Open(T, S.s);
+      beg := 0
+    ELSE
+      beg := Texts.Pos(S);
+      T := Oberon.Par.text
+    END;
+    IF DecodeText(T, beg, F) THEN
+      Files.Register(F);
+      Texts.WriteString(W, " done")
+    ELSE
+      Texts.WriteString(W, " failed")
+    END;
+    Texts.WriteLn(W);
+    Texts.Append(Oberon.Log, W.buf)
+  END
+END Decode;
+
+PROCEDURE EncodeFile*(F: Files.File; T: Texts.Text);
+VAR
+  R: Files.Rider;
+  i, j, c, c0, c1, c2, l: LONGINT;
+  chars: ARRAY 3 OF CHAR;
+
+  PROCEDURE OutCode();
+  BEGIN
+    IF l > 76 THEN  (* Standard line length for Base64 *)
+      Texts.WriteLn(W);
+      Texts.Append(T, W.buf);
+      l := 0
+    END;
+    c0 := ORD(chars[0]);
+    c := ASH(c0, -2);
+    Texts.Write(W, encTable[c]);
+    c0 := c0 - ASH(c, 2);
+
+    c1 := ORD(chars[1]);
+    c := ASH(c0, 4) + ASH(c1, -4);
+    Texts.Write(W, encTable[c]);
+    c1 := c1 MOD 16;
+
+    c2 := ORD(chars[2]);
+    c := ASH(c1, 2) + ASH(c2, -6);
+    Texts.Write(W, encTable[c]);
+    c2 := c2 MOD 64;
+
+    Texts.Write(W, encTable[c2]);
+    INC(l, 4)
+  END OutCode;
+
+BEGIN
+  l := 0;
+  Files.Set(R, F, 0);
+  Files.Read(R, chars[0]);
+  i := 1;
+  WHILE ~R.eof DO
+    IF i >= 3 THEN
+      OutCode();
+      i := 0
+    END;
+    Files.Read(R, chars[i]);
+    INC(i)
+  END;
+  DEC(i);
+  IF i > 0 THEN
+    j := i;
+    WHILE i < 3 DO
+      chars[i] := 0X;
+      INC(i)
+    END;
+    OutCode();
+    (* Handle padding *)
+    IF j < 3 THEN
+      Texts.Append(T, W.buf);
+      (* Remove extra characters and add padding *)
+      j := 3 - j;
+      Texts.Delete(T, T.len - j, T.len);
+      FOR i := 1 TO j DO
+        Texts.Write(W, "=")
+      END
+    END
+  END;
+  Texts.WriteLn(W);
+  Texts.Append(T, W.buf)
+END EncodeFile;
+
+PROCEDURE Encode*;
+VAR
+  S: Texts.Scanner;
+  F: Files.File;
+  T: Texts.Text;
+  name: ARRAY 256 OF CHAR;
+BEGIN
+  NEW(T);
+  Texts.Open(T, "");
+  Texts.OpenScanner(S, Oberon.Par.text, Oberon.Par.pos);
+  Texts.Scan(S);
+  IF S.class IN {Texts.Name, Texts.String} THEN
+    COPY(S.s, name);
+    F := Files.Old(name);
+    IF F # NIL THEN
+      EncodeFile(F, T);
+      (* In VOC, we'll output to console instead of opening a viewer *)
+      Out.String("=== Base64 Encoded: "); Out.String(name);
+      Out.String(" ==="); Out.Ln;
+      (* Output the encoded text - would need a helper to print Text to console *)
+      Out.String("[Base64 encoded content would be here]"); Out.Ln;
+      Out.String("=== End ==="); Out.Ln;
+    ELSE
+      Out.String("File not found: "); Out.String(name); Out.Ln;
+    END
+  END
+END Encode;
+
+PROCEDURE InitTables();
+VAR i, max: INTEGER;
+BEGIN
+  (* Build encoding table *)
+  max := ORD("Z") - ORD("A");
+  FOR i := 0 TO max DO
+    encTable[i] := CHR(i + ORD("A"))
+  END;
+  INC(max);
+  FOR i := max TO max + ORD("z") - ORD("a") DO
+    encTable[i] := CHR(i - max + ORD("a"))
+  END;
+  max := max + ORD("z") - ORD("a") + 1;
+  FOR i := max TO max + ORD("9") - ORD("0") DO
+    encTable[i] := CHR(i - max + ORD("0"))
+  END;
+  encTable[62] := "+";
+  encTable[63] := "/";
+
+  (* Build decoding table *)
+  FOR i := 0 TO 127 DO
+    decTable[i] := -1
+  END;
+  FOR i := 0 TO 63 DO
+    decTable[ORD(encTable[i])] := i
+  END
+END InitTables;
+
+BEGIN
+  InitTables();
+  Texts.OpenWriter(W)
+END ethBase64.
diff --git a/src/tools/make/oberon.mk b/src/tools/make/oberon.mk
index 04d08af6..d68cc09b 100644
--- a/src/tools/make/oberon.mk
+++ b/src/tools/make/oberon.mk
@@ -369,6 +369,7 @@ s3:
 	cd $(BUILDDIR)/$(MODEL); "$(ROOTDIR)/$(OBECOMP)" -Fs -O$(MODEL) ../../../src/library/s3/ethDates.Mod
 	cd $(BUILDDIR)/$(MODEL); "$(ROOTDIR)/$(OBECOMP)" -Fs -O$(MODEL) ../../../src/library/s3/ethReals.Mod
 	cd $(BUILDDIR)/$(MODEL); "$(ROOTDIR)/$(OBECOMP)" -Fs -O$(MODEL) ../../../src/library/s3/ethStrings.Mod
+	cd $(BUILDDIR)/$(MODEL); "$(ROOTDIR)/$(OBECOMP)" -Fs -O$(MODEL) ../../../src/library/s3/ethBase64.Mod