diff --git a/extmod/btstack/modbluetooth_btstack.c b/extmod/btstack/modbluetooth_btstack.c
index 97dd2cbb53..9faae26e46 100644
--- a/extmod/btstack/modbluetooth_btstack.c
+++ b/extmod/btstack/modbluetooth_btstack.c
@@ -295,20 +295,34 @@ STATIC void btstack_packet_handler(uint8_t packet_type, uint8_t *packet, uint8_t
 
     if (event_type == HCI_EVENT_LE_META) {
         DEBUG_printf("  --> hci le meta\n");
-        if (hci_event_le_meta_get_subevent_code(packet) == HCI_SUBEVENT_LE_CONNECTION_COMPLETE) {
-            uint16_t conn_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
-            uint8_t addr_type = hci_subevent_le_connection_complete_get_peer_address_type(packet);
-            bd_addr_t addr;
-            hci_subevent_le_connection_complete_get_peer_address(packet, addr);
-            uint16_t irq_event;
-            if (hci_subevent_le_connection_complete_get_role(packet) == 0) {
-                // Master role.
-                irq_event = MP_BLUETOOTH_IRQ_PERIPHERAL_CONNECT;
-            } else {
-                // Slave role.
-                irq_event = MP_BLUETOOTH_IRQ_CENTRAL_CONNECT;
+        switch (hci_event_le_meta_get_subevent_code(packet)) {
+            case HCI_SUBEVENT_LE_CONNECTION_COMPLETE: {
+                uint16_t conn_handle = hci_subevent_le_connection_complete_get_connection_handle(packet);
+                uint8_t addr_type = hci_subevent_le_connection_complete_get_peer_address_type(packet);
+                bd_addr_t addr;
+                hci_subevent_le_connection_complete_get_peer_address(packet, addr);
+                uint16_t irq_event;
+                if (hci_subevent_le_connection_complete_get_role(packet) == 0) {
+                    // Master role.
+                    irq_event = MP_BLUETOOTH_IRQ_PERIPHERAL_CONNECT;
+                } else {
+                    // Slave role.
+                    irq_event = MP_BLUETOOTH_IRQ_CENTRAL_CONNECT;
+                }
+                mp_bluetooth_gap_on_connected_disconnected(irq_event, conn_handle, addr_type, addr);
+                break;
+            }
+            case HCI_SUBEVENT_LE_CONNECTION_UPDATE_COMPLETE: {
+                uint8_t status = hci_subevent_le_connection_update_complete_get_status(packet);
+                uint16_t conn_handle = hci_subevent_le_connection_update_complete_get_connection_handle(packet);
+                uint16_t conn_interval = hci_subevent_le_connection_update_complete_get_conn_interval(packet);
+                uint16_t conn_latency = hci_subevent_le_connection_update_complete_get_conn_latency(packet);
+                uint16_t supervision_timeout = hci_subevent_le_connection_update_complete_get_supervision_timeout(packet);
+                DEBUG_printf("- LE Connection %04x: connection update - connection interval %u.%02u ms, latency %u, timeout %u\n",
+                    conn_handle, conn_interval * 125 / 100, 25 * (conn_interval & 3), conn_latency, supervision_timeout);
+                mp_bluetooth_gap_on_connection_update(conn_handle, conn_interval, conn_latency, supervision_timeout, status);
+                break;
             }
-            mp_bluetooth_gap_on_connected_disconnected(irq_event, conn_handle, addr_type, addr);
         }
     } else if (event_type == BTSTACK_EVENT_STATE) {
         uint8_t state = btstack_event_state_get_state(packet);
diff --git a/extmod/modbluetooth.c b/extmod/modbluetooth.c
index 2cff386f12..dc1084acc1 100644
--- a/extmod/modbluetooth.c
+++ b/extmod/modbluetooth.c
@@ -979,6 +979,9 @@ STATIC mp_obj_t bluetooth_ble_invoke_irq(mp_obj_t none_in) {
         if (event == MP_BLUETOOTH_IRQ_CENTRAL_CONNECT || event == MP_BLUETOOTH_IRQ_PERIPHERAL_CONNECT || event == MP_BLUETOOTH_IRQ_CENTRAL_DISCONNECT || event == MP_BLUETOOTH_IRQ_PERIPHERAL_DISCONNECT) {
             // conn_handle, addr_type, addr
             ringbuf_extract(&o->ringbuf, data_tuple, 1, 1, &o->irq_data_addr, 0, NULL, NULL);
+        } else if (event == MP_BLUETOOTH_IRQ_CONNECTION_UPDATE) {
+            // conn_handle, conn_interval, conn_latency, supervision_timeout, status
+            ringbuf_extract(&o->ringbuf, data_tuple, 5, 0, NULL, 0, NULL, NULL);
         } else if (event == MP_BLUETOOTH_IRQ_GATTS_WRITE) {
             // conn_handle, value_handle
             ringbuf_extract(&o->ringbuf, data_tuple, 2, 0, NULL, 0, NULL, NULL);
@@ -1093,6 +1096,11 @@ void mp_bluetooth_gap_on_connected_disconnected(uint8_t event, uint16_t conn_han
     invoke_irq_handler(event, &conn_handle, 1, &addr_type, 1, addr, NULL_I8, 0, NULL_UUID, NULL_DATA, 0);
 }
 
+void mp_bluetooth_gap_on_connection_update(uint16_t conn_handle, uint16_t conn_interval, uint16_t conn_latency, uint16_t supervision_timeout, uint16_t status) {
+    uint16_t args[] = {conn_handle, conn_interval, conn_latency, supervision_timeout, status};
+    invoke_irq_handler(MP_BLUETOOTH_IRQ_CONNECTION_UPDATE, args, 5, NULL_U8, 0, NULL_ADDR, NULL_I8, 0, NULL_UUID, NULL_DATA, 0);
+}
+
 void mp_bluetooth_gatts_on_write(uint16_t conn_handle, uint16_t value_handle) {
     uint16_t args[] = {conn_handle, value_handle};
     invoke_irq_handler(MP_BLUETOOTH_IRQ_GATTS_WRITE, args, 2, NULL_U8, 0, NULL_ADDR, NULL_I8, 0, NULL_UUID, NULL_DATA, 0);
@@ -1276,6 +1284,19 @@ void mp_bluetooth_gap_on_connected_disconnected(uint8_t event, uint16_t conn_han
     schedule_ringbuf(atomic_state);
 }
 
+void mp_bluetooth_gap_on_connection_update(uint16_t conn_handle, uint16_t conn_interval, uint16_t conn_latency, uint16_t supervision_timeout, uint16_t status) {
+    MICROPY_PY_BLUETOOTH_ENTER
+    mp_obj_bluetooth_ble_t *o = MP_OBJ_TO_PTR(MP_STATE_VM(bluetooth));
+    if (enqueue_irq(o, 2 + 2 + 2 + 2 + 2, MP_BLUETOOTH_IRQ_CONNECTION_UPDATE)) {
+        ringbuf_put16(&o->ringbuf, conn_handle);
+        ringbuf_put16(&o->ringbuf, conn_interval);
+        ringbuf_put16(&o->ringbuf, conn_latency);
+        ringbuf_put16(&o->ringbuf, supervision_timeout);
+        ringbuf_put16(&o->ringbuf, status);
+    }
+    schedule_ringbuf(atomic_state);
+}
+
 void mp_bluetooth_gatts_on_write(uint16_t conn_handle, uint16_t value_handle) {
     MICROPY_PY_BLUETOOTH_ENTER
     mp_obj_bluetooth_ble_t *o = MP_OBJ_TO_PTR(MP_STATE_VM(bluetooth));
diff --git a/extmod/modbluetooth.h b/extmod/modbluetooth.h
index 9caddb0f3f..2619e71894 100644
--- a/extmod/modbluetooth.h
+++ b/extmod/modbluetooth.h
@@ -114,6 +114,7 @@
 #define MP_BLUETOOTH_IRQ_L2CAP_DISCONNECT               (24)
 #define MP_BLUETOOTH_IRQ_L2CAP_RECV                     (25)
 #define MP_BLUETOOTH_IRQ_L2CAP_SEND_READY               (26)
+#define MP_BLUETOOTH_IRQ_CONNECTION_UPDATE              (27)
 
 #define MP_BLUETOOTH_ADDRESS_MODE_PUBLIC (0)
 #define MP_BLUETOOTH_ADDRESS_MODE_RANDOM (1)
@@ -151,6 +152,7 @@ _IRQ_L2CAP_CONNECT = const(23)
 _IRQ_L2CAP_DISCONNECT = const(24)
 _IRQ_L2CAP_RECV = const(25)
 _IRQ_L2CAP_SEND_READY = const(26)
+_IRQ_GATTS_CONN_UPDATE = const(27)
 */
 
 // bluetooth.UUID type.
@@ -281,6 +283,9 @@ int mp_bluetooth_l2cap_recvinto(uint16_t conn_handle, uint16_t cid, uint8_t *buf
 // Notify modbluetooth that a connection/disconnection event has occurred.
 void mp_bluetooth_gap_on_connected_disconnected(uint8_t event, uint16_t conn_handle, uint8_t addr_type, const uint8_t *addr);
 
+// Call this when any connection parameters have been changed.
+void mp_bluetooth_gap_on_connection_update(uint16_t conn_handle, uint16_t conn_interval, uint16_t conn_latency, uint16_t supervision_timeout, uint16_t status);
+
 // Call this when a characteristic is written to.
 void mp_bluetooth_gatts_on_write(uint16_t conn_handle, uint16_t value_handle);
 
diff --git a/extmod/nimble/modbluetooth_nimble.c b/extmod/nimble/modbluetooth_nimble.c
index e4a048e3d3..3983d18690 100644
--- a/extmod/nimble/modbluetooth_nimble.c
+++ b/extmod/nimble/modbluetooth_nimble.c
@@ -303,6 +303,19 @@ STATIC int gap_event_cb(struct ble_gap_event *event, void *arg) {
             }
             break;
         }
+
+        case BLE_GAP_EVENT_PHY_UPDATE_COMPLETE:
+            DEBUG_printf("gap_event_cb: phy update: %d\n", event->phy_updated.tx_phy);
+            break;
+
+        case BLE_GAP_EVENT_CONN_UPDATE: {
+            DEBUG_printf("gap_event_cb: connection update: status=%d\n", event->conn_update.status);
+            struct ble_gap_conn_desc desc;
+            if (ble_gap_conn_find(event->conn_update.conn_handle, &desc) == 0) {
+                mp_bluetooth_gap_on_connection_update(event->conn_update.conn_handle, desc.conn_itvl, desc.conn_latency, desc.supervision_timeout, event->conn_update.status == 0 ? 0 : 1);
+            }
+            break;
+        }
     }
     return 0;
 }
@@ -938,13 +951,13 @@ STATIC int peripheral_gap_event_cb(struct ble_gap_event *event, void *arg) {
             break;
         }
 
-        case BLE_GAP_EVENT_CONN_UPDATE:
-            // TODO
-            break;
-
-        case BLE_GAP_EVENT_CONN_UPDATE_REQ:
-            // TODO
+        case BLE_GAP_EVENT_CONN_UPDATE: {
+            DEBUG_printf("peripheral_gap_event_cb: connection update: status=%d\n", event->conn_update.status);
+            if (ble_gap_conn_find(event->conn_update.conn_handle, &desc) == 0) {
+                mp_bluetooth_gap_on_connection_update(event->conn_update.conn_handle, desc.conn_itvl, desc.conn_latency, desc.supervision_timeout, event->conn_update.status == 0 ? 0 : 1);
+            }
             break;
+        }
 
         case BLE_GAP_EVENT_MTU: {
             if (event->mtu.channel_id == BLE_L2CAP_CID_ATT) {