diff --git a/spynnaker/pyNN/connections/spynnaker_poisson_control_connection.py b/spynnaker/pyNN/connections/spynnaker_poisson_control_connection.py
index 5a969fd571..64a840b2b8 100644
--- a/spynnaker/pyNN/connections/spynnaker_poisson_control_connection.py
+++ b/spynnaker/pyNN/connections/spynnaker_poisson_control_connection.py
@@ -105,20 +105,22 @@ def __init_callback_wrapper(
                  machine_timestep_ms)
 
     @overrides(LiveEventConnection.add_start_callback)
-    def add_start_callback(self, label: str, start_callback: _Callback):
+    def add_start_callback(
+            self, label: str, start_callback: _Callback) -> None:
         super().add_start_callback(
             self.__control_label(label), functools.partial(
                 self.__callback_wrapper, start_callback))
 
     @overrides(LiveEventConnection.add_start_resume_callback)
     def add_start_resume_callback(
-            self, label: str, start_resume_callback: _Callback):
+            self, label: str, start_resume_callback: _Callback) -> None:
         super().add_start_resume_callback(
             self.__control_label(label), functools.partial(
                 self.__callback_wrapper, start_resume_callback))
 
     @overrides(LiveEventConnection.add_init_callback)
-    def add_init_callback(self, label: str, init_callback: _InitCallback):
+    def add_init_callback(
+            self, label: str, init_callback: _InitCallback) -> None:
         super().add_init_callback(
             self.__control_label(label), functools.partial(
                 self.__init_callback_wrapper, init_callback))
@@ -126,20 +128,20 @@ def add_init_callback(self, label: str, init_callback: _InitCallback):
     @overrides(LiveEventConnection.add_receive_callback)
     def add_receive_callback(
             self, label: str, live_event_callback: _RcvTimeCallback,
-            translate_key: bool = True):
+            translate_key: bool = True) -> None:
         raise ConfigurationException(
             "SpynnakerPoissonControlPopulation can't receive data")
 
     @overrides(LiveEventConnection.add_receive_no_time_callback)
     def add_receive_no_time_callback(
             self, label: str, live_event_callback: _RcvCallback,
-            translate_key: bool = True):
+            translate_key: bool = True) -> None:
         raise ConfigurationException(
             "SpynnakerPoissonControlPopulation can't receive data")
 
     @overrides(LiveEventConnection.add_pause_stop_callback)
     def add_pause_stop_callback(
-            self, label: str, pause_stop_callback: _Callback):
+            self, label: str, pause_stop_callback: _Callback) -> None:
         super().add_pause_stop_callback(
             self.__control_label(label), functools.partial(
                 self.__callback_wrapper, pause_stop_callback))
diff --git a/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py b/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py
index 3901d99a88..7f50a095ae 100644
--- a/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py
+++ b/spynnaker/pyNN/models/utility_models/delays/delay_extension_machine_vertex.py
@@ -147,7 +147,7 @@ def sdram_required(self) -> AbstractSDRAM:
                parse_extra_provenance_items)
     def parse_extra_provenance_items(
             self, label: str, x: int, y: int, p: int,
-            provenance_data: Sequence[int]):
+            provenance_data: Sequence[int]) -> None:
         (n_received, n_processed, n_added, n_sent, n_overflows, n_delays,
          n_sat, n_bad_neuron, n_bad_keys, n_late_spikes, max_bg,
          n_bg_overloads) = provenance_data