Add timer that updates the read attributes at 2Hz. One has the value of SW1,...

Add timer that updates the read attributes at 2Hz. One has the value of SW1, the other has a RNG value.

blechat.py

 import pyb
 import network
+import micropython
 
 class BleChat:
     def __init__(self, name):
         self.name = name
         self.local_name = None
         self.local_mac = None
+        self.write_handle = None
+        self.read_sw_handle = None
+        self.read_rand_handle = None
 
-        self.rs = network.RS911XBT(pyb.SPI(2), pyb.Pin("I0"), pyb.Pin("E3"), pyb.Pin("E4"))
+        self.rs = network.RS9116()
+        self.rs.init()
         self.lcd = pyb.LCD()
         self.led = pyb.LED(1)
+        self.tim = pyb.Timer(4)
+
+        self._set_attr = self._set_attr_method
 
         self._hardware_setup()
         self._radio_setup()
+        self._timer_setup()
+
+    def _timer_setup(self):
+        self.tim.init(freq=2)
+        self.tim.callback(self._timer_callback)
+
+    def _timer_callback(self, tim):
+        micropython.schedule(self._set_attr, 0)
+
+    def _set_attr_method(self, _):
+        self.rs.set_attr_value(self.read_sw_handle, "Pressed" if pyb.Switch(1).value() else "Not Pressed")
+        self.rs.set_attr_value(self.read_rand_handle, "{}".format(pyb.rng()))
 
     def _radio_setup(self):
         handle = self.rs.add_service(0xaabb)
         # write_attr_index = rs.add_attribute(handle, 0x1aa2, rs.ATT_PROPERTY_WRITE)
         # read_attr_index = rs.add_attribute(handle, 0x2bb1, rs.ATT_PROPERTY_NOTIFY | rs.ATT_PROPERTY_READ)
-        self.rs.add_attribute(handle, 0x1aa2, self.rs.ATT_PROPERTY_WRITE)
-        self.rs.add_attribute(handle, 0x2bb1, self.rs.ATT_PROPERTY_NOTIFY | self.rs.ATT_PROPERTY_READ)
+        self.write_handle = self.rs.add_attribute(handle, 0x1aa2, self.rs.ATT_PROPERTY_WRITE)
+        self.read_sw_handle = self.rs.add_attribute(handle, 0x2bb1, self.rs.ATT_PROPERTY_NOTIFY | self.rs.ATT_PROPERTY_READ)
+        self.read_rand_handle = self.rs.add_attribute(handle, 0x3cc4, self.rs.ATT_PROPERTY_READ)
         self.rs.set_antenna(self.rs.INTERNAL_ANTENNA)
         self.rs.set_adv_data(self.name)
         self.rs.set_scan_resp_data(self.name)