def __init__(self, channel_access, pv):
"""
Initialise.
Args:
channel_access: channel_access to set up monitor
pv: name of pv to monitor
"""
self.pv = pv
self._full_pv_name = channel_access.create_pv_with_prefix(pv)
self.all_values = []
self.latest_value = None
CaChannelWrapper.add_monitor(channel_access.create_pv_with_prefix(pv),
self._set_val)
