class BEE2CorrelationProvider(BasicCorrelationProvider):
""" Connects to an a running instance of 'tcpborphserver'
attached to a single BEE2 corner chip, reads off correlation
functions for the requested set of baselines, and sends them
over UDP packets to registered subscribers. See 'backends.basic.
BasicCorrelationProvider' for more detail."""
def __init__(self, server, include_baselines,
bee2_host, bee2_port, lags=32,
bof='bee2_calib_corr.bof'):
""" Overloaded method which adds some arguments necessary
for connecting to 'tcpborphserver' running on a BEE2."""
BasicCorrelationProvider.__init__(self, server, include_baselines, lags)
self.bee2_host = bee2_host
self.bee2_port = bee2_port
self.bee2 = FpgaClient(bee2_host, port=bee2_port)
self.bee2._connected.wait()
self._program(bof)
self.bee2.write_int('start', 1)
def _program(self, bof):
""" Update the list of available bitstreams and program
the BEE2 corner chip with the requested image."""
self.logger.debug("_program('%s')" %bof)
self.bofs = self.bee2.listbof()
if bof in self.bofs:
self.bee2.progdev(bof)
self.logger.info("successfully programmed '%s'" %bof)
else:
err_msg = "'%s' not available! Check the BOF path." %bof
self.logger.error(err_msg)
raise BEE2BorphError(err_msg)
def correlate(self):
""" This overloads 'BasicCorrelationProvider.correlate'
(which does nothing) and enables/resets correlations on
the BEE2 corner chip as well as setting integration times,
etc. It then reads the correlations and stores them to be
broadcast to its list of subscribers."""
self.logger.debug('correlate()')
integration_time = self.server._integration_time
self.logger.info("correlating for %0.2f seconds" %integration_time)
self.bee2.write_int('hb_cntto', integration_time+1)
for baseline in self._include_baselines:
raw = self.bee2.read('corr_out%d' %(int(baseline[1])-1), 128)
self._correlations[baseline] = array(CORR_OUT.unpack(raw))
self.logger.info('baseline %s, mean %d' %(baseline, self._correlations[baseline].mean()))
self.bee2.write_int('corr_record', 0)
self.bee2.write_int('corr_en', 0)
self.bee2.write_int('corr_rst', 1)
self.bee2.write_int('corr_rst', 0)
self.bee2.write_int('corr_en', 1)
sleep(integration_time+1)
self.bee2.write_int('corr_record', 1)
