ti84: allow case select during a-lock with 2nd mode

blk/570

@@ -7,5 +7,8 @@
             IF _tbl^ _2nd@ IF _alock^ THEN THEN
         SWAP 0x81 = _2nd!
         _gti + C@
-    DUP 0 0x80 >< UNTIL ( loop if not in range ) ;
+    DUP 0 0x80 >< UNTIL ( loop if not in range )
+    ( lowercase? )
+    _2nd@ IF DUP 'A' 'Z' =><= IF 0x20 OR THEN THEN
+;
 : KBD$ 0 [ KBD_MEM LITN ] C! ;