frappy/frappy_psi/ah2700.py
Markus Zolliker 8b27e4012c frappy_psi.ah2700: auto create loss module with Pinata
the loss angle is a separate quantity, which is preferred to
be an extra module. create this automatically.

Change-Id: I97f6be48f3411d8143f2ff85c2c61711fc71e8d6
Reviewed-on: https://forge.frm2.tum.de/review/c/secop/frappy/+/33908
Tested-by: Jenkins Automated Tests <pedersen+jenkins@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
2024-06-17 15:20:21 +02:00

129 lines
4.7 KiB
Python

#!/usr/bin/env python
# *****************************************************************************
# This program is free software; you can redistribute it and/or modify it under
# the terms of the GNU General Public License as published by the Free Software
# Foundation; either version 2 of the License, or (at your option) any later
# version.
#
# This program is distributed in the hope that it will be useful, but WITHOUT
# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
# FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
# details.
#
# You should have received a copy of the GNU General Public License along with
# this program; if not, write to the Free Software Foundation, Inc.,
# 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
#
# Module authors:
# Markus Zolliker <markus.zolliker@psi.ch>
# *****************************************************************************
"""Andeen Hagerling capacitance bridge
two modules: the capacitance itself and the loss angle
in the configuration file, only the capacitance module needs to be configured,
while the loss module will be created automatically.
the name of the loss module may be configured, or disabled by choosing
an empty name
"""
from frappy.core import FloatRange, HasIO, Parameter, Readable, StringIO, nopoll, \
Attached, Property, StringType
from frappy.dynamic import Pinata
class Ah2700IO(StringIO):
end_of_line = '\r\n'
timeout = 5
class Capacitance(HasIO, Pinata, Readable):
value = Parameter('capacitance', FloatRange(unit='pF'))
freq = Parameter('frequency', FloatRange(unit='Hz'), readonly=False, default=0)
voltage = Parameter('voltage', FloatRange(unit='V'), readonly=False, default=0)
loss_name = Property('''name of loss module (default: <name>_loss)
configure '' to disable the creation of the loss module
''',
StringType(), default='$_loss')
ioClass = Ah2700IO
loss = 0 # not a parameter
def scanModules(self):
if self.loss_name:
# if loss_name is not empty, we tell the framework to create
# a module for the loss with this name, and config below
yield self.loss_name.replace('$', self.name), {
'cls': Loss,
'description': f'loss value of {self.name}',
'cap': self.name}
def parse_reply(self, reply):
if reply.startswith('SI'): # this is an echo
self.communicate('SERIAL ECHO OFF')
reply = self.communicate('SI')
if not reply.startswith('F='): # this is probably an error message like "LOSS TOO HIGH"
self.status = self.Status.ERROR, reply
return self.value
self.status = self.Status.IDLE, ''
# examples of replies:
# 'F= 1000.0 HZ C= 0.000001 PF L> 0.0 DS V= 15.0 V'
# 'F= 1000.0 HZ C= 0.0000059 PF L=-0.4 DS V= 15.0 V OVEN'
# 'LOSS TOO HIGH'
# make sure there is always a space after '=' and '>'
# split() ignores multiple white space
reply = reply.replace('=', '= ').replace('>', '> ').split()
_, freq, _, _, cap, _, _, loss, lossunit, _, volt = reply[:11]
self.freq = freq
self.voltage = volt
if lossunit == 'DS':
self.loss = loss
else: # the unit was wrong, we want DS = tan(delta), not NS = nanoSiemens
reply = self.communicate('UN DS').split() # UN DS returns a reply similar to SI
try:
self.loss = reply[7]
except IndexError:
pass # don't worry, loss will be updated next time
return cap
def read_value(self):
return self.parse_reply(self.communicate('SI')) # SI = single trigger
@nopoll
def read_freq(self):
self.read_value()
return self.freq
@nopoll
def read_voltage(self):
self.read_value()
return self.voltage
def write_freq(self, value):
self.value = self.parse_reply(self.communicate(f'FR {value:g};SI'))
return self.freq
def write_voltage(self, value):
self.value = self.parse_reply(self.communicate(f'V {value:g};SI'))
return self.voltage
class Loss(Readable):
cap = Attached()
value = Parameter('loss', FloatRange(unit='deg'), default=0)
def initModule(self):
super().initModule()
self.cap.registerCallbacks(self, ['status']) # auto update status
def update_value(self, _):
# value is always changed shortly after loss
self.value = self.cap.loss
@nopoll
def read_value(self):
self.cap.read_value()
return self.cap.loss