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+Imlac Assembler (iasm)
+======================
+
+The code here is an Imlac assembler that takes an Imlac assembler file and
+generates a patertape file including the bootstrap loader.  Optionally,
+a listing file can also be produced.
+
+    Usage: iasm <option> <filename>                                           
+
+    where <option>   is zero or more of                                       
+                       -bptr     use a papertape boot loader                  
+                       -btty     use a teletype boot loader                   
+                       -l <file> write listing to file <file>                 
+          <filename> is the file to assemble.                                 
+
+    The input filename has the form of 'file.asm' and                         
+    the output file will be 'file.ptp' or 'file.tty'.