diff --git a/erlang/apps/sim/src/sim_core.erl b/erlang/apps/sim/src/sim_core.erl
index 3af4f9b..5b8a7dd 100644
--- a/erlang/apps/sim/src/sim_core.erl
+++ b/erlang/apps/sim/src/sim_core.erl
@@ -241,6 +241,7 @@ dispatch(Core, Mem, IR, EA) ->
     8#207 -> sim_moves:handle_MOVSS(Core, Mem, IR, EA);
     8#210 -> sim_moves:handle_MOVN(Core, Mem, IR, EA);
     8#211 -> sim_moves:handle_MOVNI(Core, Mem, IR, EA);
+    8#212 -> sim_moves:handle_MOVNM(Core, Mem, IR, EA);
     8#250 -> sim_moves:handle_EXCH(Core, Mem, IR, EA);
     _ ->
       PC = (Core#core.pc_section bsl 18) bor Core#core.pc_offset,
diff --git a/erlang/apps/sim/src/sim_moves.erl b/erlang/apps/sim/src/sim_moves.erl
index aef7796..a39a4a9 100644
--- a/erlang/apps/sim/src/sim_moves.erl
+++ b/erlang/apps/sim/src/sim_moves.erl
@@ -31,6 +31,7 @@
         , handle_MOVES/4
         , handle_MOVN/4
         , handle_MOVNI/4
+        , handle_MOVNM/4
         , handle_MOVS/4
         , handle_MOVSI/4
         , handle_MOVSM/4
@@ -182,6 +183,28 @@ handle_MOVNI(Core, Mem, IR, #ea{offset = E}) ->
   AC = IR band 8#17,
   sim_core:next_pc(sim_core:set_ac(Core, AC, (-E) band ((1 bsl 36) - 1)), Mem).
 
+-spec handle_MOVNM(#core{}, sim_mem:mem(), IR :: word(), #ea{})
+      -> {#core{}, sim_mem:mem(), {ok, integer()} | {error, {module(), term()}}}.
+handle_MOVNM(Core, Mem, IR, EA) ->
+  AC = IR band 8#17,
+  CA = sim_core:get_ac(Core, AC),
+  {Negated, Flags} = negate(CA),
+  handle_MOVNM(Core, Mem, Negated, Flags, EA).
+
+handle_MOVNM(Core, Mem, Word, Flags, EA) ->
+  %% "2.9.6.1 Overflow Trapping in the KL10, KS10, and KI10 Processors" and
+  %% "2.9.6.2 Overflow Trapping in the XKL-1 Processor" both state that if
+  %% an instruction causes both overflow and a page failure, the page failure
+  %% is handled first, and the overflow trap is handled after the instruction
+  %% has restarted and completed.
+  %% Therefore complete the store before updating flags and proceeding.
+  case sim_core:cset(Core, Mem, EA, Word) of
+    {ok, Core1} -> sim_core:next_pc(sim_core:set_flags(Core1, Flags), Mem);
+    {error, Reason} ->
+      sim_core:page_fault(Core, Mem, ea_address(EA), write, Reason,
+                          fun(Core1, Mem1) -> handle_MOVNM(Core1, Mem1, Word, Flags, EA) end)
+  end.
+
 %% Miscellaneous ===============================================================
 
 ea_address(#ea{section = Section, offset = Offset}) ->
diff --git a/erlang/apps/sim/test/sim_moves_tests.erl b/erlang/apps/sim/test/sim_moves_tests.erl
index 9934100..f9b0213 100644
--- a/erlang/apps/sim/test/sim_moves_tests.erl
+++ b/erlang/apps/sim/test/sim_moves_tests.erl
@@ -53,6 +53,7 @@
 -define(OP_MOVSS, 8#207).
 -define(OP_MOVN, 8#210).
 -define(OP_MOVNI, 8#211).
+-define(OP_MOVNM, 8#212).
 -define(OP_EXCH, 8#250).
 
 %% 2.1.1 Exchange Instruction ==================================================
@@ -234,6 +235,17 @@ movni_test() ->
          [ {#ea{section = 1, offset = 1, islocal = false}, (-8#42) band ((1 bsl 36) - 1)} % AC1 = -42
          ]).
 
+movnm_test() ->
+  Prog =
+    [ {1, 8#100, ?INSN(?OP_MOVEI, 1, 0, 0, 8#42)}   % 1,,100/ MOVEI 1,42
+    , {1, 8#101, ?INSN(?OP_MOVNM, 1, 0, 0, 8#150)}  % 1,,101/ MOVNM 1,150
+    , {1, 8#102, ?INSN_INVALID}                     % 1,,102/ <invalid>
+    , {1, 8#150, 8#27}                              % 1,,150/ 0,,27
+    ],
+  expect(Prog, [], {1, 8#102}, ?DEFAULT_FLAGS,
+         [ {#ea{section = 1, offset = 8#150, islocal = false}, (-8#42) band ((1 bsl 36) - 1)} % C(1,,150) = -42
+         ]).
+
 %% Common code to run short sequences ==========================================
 
 expect(Prog, ACs, ExpectedPC, ExpectedFlags, ExpectedEs) ->