Signals in labrad

How to emit a signal in a server

Import Signal class from labrad.server import Signal Create Signal object. onEvent = Signal( ID, signal name, data_type) #i.e ID = 543617 #name = 'signal: interesting information acquired' #info_type = 'i' for integer data Note this has to be done as a global class variable, i.e

class ourserver( LabradServer): onEvent = ... ... def initServer(self): ... Call that signal: onEvent( data, listeners) #i.e data = 34 #i.e listeners = None if message is sent to everyone listening #or listeners = set(context.ID) to send to a particular listener of that context Even if signal requires no parameters, still need to do self.onEvent(None). [edit] How to receive a singal in a simple client

import labrad from labrad.wrappers import connectAsync from twisted.internet.defer import inlineCallbacks, returnValue from twisted.internet import reactor @inlineCallbacks def connect(): def printSignal(x,y): print x,y reactor.stop() cxn = yield connectAsync() server = yield cxn.data_vault #context = yield cxn.context() yield dv.signal__new_dataset(99901)#, context = context) yield dv.addListener(listener = printSignal, source = None, ID = 99901)#, context = context) print 'now listening' reactor.callWhenRunning(connect) reactor.run()