This is the entire code. Thanks for the help.

import cb import ui class MyCentralManagerDelegateView (ui.View): def __init__(self): self.peripheral = None self.charactetistic= None self.b=ui.Button(title='button') self.add_subview(self.b) self.b.action=self.a self.frame=(0,0,320,570) def did_discover_peripheral(self, p): if p.name == 'Bluno' and not self.peripheral: print ('Discovered ')+ p.name self.peripheral = p cb.connect_peripheral(self.peripheral) def did_connect_peripheral(self, p): print ('Connected Peripheral ') + p.name print ('Looking for Service FFE0') p.discover_services() def did_discover_services(self, p, error): for s in p.services: if s.uuid == 'DFB0': print ('Found Service ') + s.uuid print ('Looking for Characteristic FFE1') p.discover_characteristics(s) def did_discover_characteristics(self, s, error): for c in s.characteristics: if c.uuid == 'DFB1': print ('Found Characteristic') + c.uuid self.characteristic=c print ('Writing H') def a(self,sender): c=self.characteristic self.peripheral.write_characteristic_value(c, 'H', False) def close(self): cb.reset() v=MyCentralManagerDelegateView() cb.set_central_delegate( v) print ('Looking for HM-10-BLE module') cb.scan_for_peripherals() v.present('sheet')```