fix firmata sketch issue

Author: hathach

libraries/Bluefruit52Lib/keywords.txt

@@ -423,6 +423,11 @@ BLE_PRPH_MAX_CONN	LITERAL1
 
 BLE_CONN_HANDLE_INVALID	LITERAL1
 
+BANDWIDTH_AUTO	LITERAL1
+BANDWIDTH_LOW	LITERAL1
+BANDWIDTH_NORMAL	LITERAL1
+BANDWIDTH_HIGH	LITERAL1
+BANDWIDTH_MAX	LITERAL1
 
 #######################################
 # Characteristic Constants (LITERAL1)

libraries/Bluefruit52Lib/src/BLEGap.cpp

@@ -40,13 +40,14 @@ BLEGap::BLEGap(void)
 {
   memclr(_peers, sizeof(_peers));
 
-#if SD_VER >= 500
   _cfg_prph.mtu_max         = BLE_GATT_ATT_MTU_DEFAULT;
+  _cfg_central.mtu_max      = BLE_GATT_ATT_MTU_DEFAULT;
+
+#if SD_VER >= 500
   _cfg_prph.event_len       = BLE_GAP_EVENT_LENGTH_DEFAULT;
   _cfg_prph.hvn_tx_qsize    = BLE_GATTS_HVN_TX_QUEUE_SIZE_DEFAULT;
   _cfg_prph.wr_cmd_qsize    = BLE_GATTC_WRITE_CMD_TX_QUEUE_SIZE_DEFAULT;
 
-  _cfg_central.mtu_max      = BLE_GATT_ATT_MTU_DEFAULT;
   _cfg_central.event_len    = BLE_GAP_EVENT_LENGTH_DEFAULT;
   _cfg_central.hvn_tx_qsize = BLE_GATTS_HVN_TX_QUEUE_SIZE_DEFAULT;
   _cfg_central.wr_cmd_qsize = BLE_GATTC_WRITE_CMD_TX_QUEUE_SIZE_DEFAULT;

libraries/Bluefruit52Lib/src/services/BLEUart.cpp

@@ -219,7 +219,7 @@ void BLEUart::_disconnect_cb(void)
 
 void BLEUart::_connect_cb (void)
 {
-  if ( _tx_buffered)
+  if ( _tx_buffered )
   {
     // create TXD timer TODO take connInterval into account
     // ((5*ms2tick(Bluefruit.connInterval())) / 4) / 2
@@ -257,6 +257,9 @@ size_t BLEUart::write (const uint8_t *content, size_t len)
     return _txd.notify(content, len) ? len : 0;
   }else
   {
+    // skip if not enabled
+    if ( !notifyEnabled() ) return 0;
+
     uint16_t written = _tx_fifo->write(content, len);
 
     // TODO multiple prph connections