diff --git a/tools/makeadf/Makefile b/tools/makeadf/Makefile
index 83b2e1d..e475355 100644
--- a/tools/makeadf/Makefile
+++ b/tools/makeadf/Makefile
@@ -6,6 +6,7 @@ include ../../shared/tools.mk
 test: $(PROGRAM)
 	$(PROGRAM) reference/bootblock.bin > out/test.adf
 	diff reference/test.adf out/test.adf
+	$(PROGRAM) reference/big.bin > out/big.adf; if [ $$? -eq 2 ] ; then echo "Correctly determined that inut will not fit on a floppy..."; else (exit 2); fi 
 	@echo "______  ___   _____ _____ ___________  "
 	@echo "| ___ \/ _ \ /  ___/  ___|  ___|  _  \ "
 	@echo "| |_/ / /_\ \\\\\ \`--.\ \`--.| |__ | | | | "
diff --git a/tools/makeadf/README.md b/tools/makeadf/README.md
index 7cb5cb9..55ba31e 100644
--- a/tools/makeadf/README.md
+++ b/tools/makeadf/README.md
@@ -6,3 +6,5 @@ The simplest form of ADF creation.
 Disk layout must be handled by the assembler/linker.  This tool only calculates the checksum and pads the disk image to the correct size.
 
 This code is taken from [this forum post](http://eab.abime.net/showpost.php?p=895070&postcount=6)
+
+Slightly modified to bork if the input file exceeds the standard amiga disk size.
diff --git a/tools/makeadf/makeadf.c b/tools/makeadf/makeadf.c
index 84d40b6..b0148f2 100644
--- a/tools/makeadf/makeadf.c
+++ b/tools/makeadf/makeadf.c
@@ -45,22 +45,28 @@ int main(int argc,char *argv[])
   if (argc == 2) {
     if ((f = fopen(argv[1],"rb"))) {
       len = fread(image,1,DISKSIZE,f);
-      if (len > 0) {
-        if (len < DISKSIZE) {
-          memset(image+len,0,DISKSIZE-len);
+      char temp;
+      if (fread(&temp,1,1,f) != 0) {
+	fprintf(stderr, "%s: input data will not fit on a floppy!\n", argv[0]);
+	rc = 2;
+      } else {
+	if (len > 0) {
+	  if (len < DISKSIZE) {
+	    memset(image+len,0,DISKSIZE-len);
+	  }
+	  boot_chksum(image);
+	  fwrite(image,1,DISKSIZE,stdout);
+	  rc = 0;
+	} else {
+	  fprintf(stderr,"%s: image read error!\n", argv[0]);
 	}
-        boot_chksum(image);
-        fwrite(image,1,DISKSIZE,stdout);
-        rc = 0;
       }
-      else
-        fprintf(stderr,"%s: image read error!\n", argv[0]);
-    }
-    else
+    } else {
       fprintf(stderr,"%s: file to open open %s\n", argv[0], argv[1]);  
-  }
-  else
+    }
+  } else {
     fprintf(stderr,"usage: %s <image data>\n", argv[0]);
+  }
 
   return rc;
 }
diff --git a/tools/makeadf/reference/big.bin b/tools/makeadf/reference/big.bin
new file mode 100755
index 0000000..e664237
Binary files /dev/null and b/tools/makeadf/reference/big.bin differ