Set time support in Application

Adds a convenience function to set the time from a python datetime
object. The time needs to be converted to TAI format which is now 35.
This number needs to be bumbed if more leap seconds are added to UTC.

ant/fs/manager.py

@@ -23,6 +23,7 @@
 from __future__ import absolute_import, print_function, division
 
 import array
+import datetime
 import logging
 import threading
 
@@ -42,7 +43,7 @@
                             AuthenticateCommand, AuthenticateResponse, DisconnectCommand,
                             UploadRequest, UploadResponse, UploadDataCommand, UploadDataResponse,
                             EraseRequestCommand, EraseResponse)
-from ant.fs.commandpipe import CreateFile, Response
+from ant.fs.commandpipe import CreateFile, Response, Time, TimeResponse
 from ant.fs.file import Directory
 from ant.fs.commons import crc
 
@@ -82,11 +83,15 @@ def __init__(self, error, errno=None):
         AntFSException.__init__(self, error, errno)
 
 
-class AntFSCreateFileException():
+class AntFSCreateFileException(AntFSException):
     def __init__(self, error, errno=None):
         AntFSException.__init__(self, error, errno)
 
 
+class AntFSTimeException(AntFSException):
+    def __init__(self, error, errno=None):
+        AntFSException.__init__(self, error, errno)
+
 class Application:
     _serial_number = 1337
     _frequency = 19  # 0 to 124, x - 2400 (in MHz)
@@ -332,6 +337,20 @@ def download_directory(self, callback=None):
         data = self.download(0, callback)
         return Directory.parse(data)
 
+    def set_time(self, time=datetime.datetime.utcnow()):
+        """
+        :param time: datetime in UTC, or None to set to current time
+        """
+        utc_tai_diff_seconds = 35
+        offset = time - datetime.datetime(1989, 12, 31, 0, 0, 0)
+        t = Time(int(offset.total_seconds()) + utc_tai_diff_seconds, 0xffffffff, 0)
+        self._send_commandpipe(t.get())
+
+        result = self._get_commandpipe()
+
+        if result.get_response() != TimeResponse.Response.OK:
+            raise AntFSTimeException("Failed to set time", result.get_response())
+
     def erase(self, index):
         self._send_command(EraseRequestCommand(index))
         response = self._get_command()

examples/antfs_list.py

@@ -22,14 +22,12 @@
 
 from __future__ import absolute_import, print_function
 
-from ant.fs.manager import Application, AntFSAuthenticationException
-from ant.fs.commandpipe import Time
 import logging
-import datetime
 
+from ant.fs.manager import Application, AntFSAuthenticationException, AntFSTimeException
 
-class Listener(Application):
 
+class Listener(Application):
     def __init__(self):
         Application.__init__(self)
 
@@ -39,33 +37,30 @@ def setup_channel(self, channel):
         channel.set_rf_freq(50)
         channel.set_search_waveform([0x53, 0x00])
         channel.set_id(0, 0x01, 0)
-        
+
         channel.open()
-        
+
         print("Lister: Searching for devices...")
-    
+
     def on_link(self, beacon):
         print("Lister: Link", beacon.get_serial(), beacon.get_descriptor())
         self.link()
         return True
-    
+
     def on_authentication(self, beacon):
         print("Lister: Auth", self.authentication_serial())
         try:
             self.authentication_pair("ANT-FS List")
             return True
         except AntFSAuthenticationException as e:
             return False
-    
+
     def on_transport(self, beacon):
-        x = datetime.datetime.now() - datetime.datetime(1989, 12, 31, 0, 0, 0)
-        t = Time(int(x.total_seconds()), 0xffffffff, 0)
-
-        self._send_commandpipe(t.get())
-        result = self._get_commandpipe()
-
-        print("Time, response:", result.get_request_id(), result.get_response())
-
+        try:
+            self.set_time()
+        except AntFSTimeException:
+            print("Could not set time")
+
         print("Listener: Transport")
         directory = self.download_directory()
         print("Directory version:      ", directory.get_version())
@@ -76,7 +71,6 @@ def on_transport(self, beacon):
 
 
 def main():
-
     logging.basicConfig()
 
     try:
@@ -89,7 +83,8 @@ def main():
     finally:
         print("Stop")
         # a.stop()
-
+
+
 if __name__ == "__main__":
     main()