#!/usr/bin/env python # -*- coding: utf-8 -*- # ***************************************************************************** # 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: # Daniel Margineda , Oksana Shliakhtun # ***************************************************************************** """Signal Recovery SR7270: lockin amplifier for AC susceptibility""" from frappy.core import Readable, Parameter, FloatRange, TupleOf, \ HasIO, StringIO, IntRange, BoolType, Writable, EnumType from frappy.errors import RangeError class SR_IO(StringIO): end_of_line = b'\x00' identification = [('ID', r'.*')] # Identification; causes the lock-in amplifier to respond with the number 7270 def communicate(self, cmd): # remove dash from terminator reply = super().communicate(cmd) status = self._conn.readbytes(2, timeout=0.1) # get the 2 status bytes return reply + ';%d;%d' % tuple(status) class XY(HasIO, Readable): value = Parameter('X, Y', datatype=TupleOf(FloatRange(unit='V'), FloatRange(unit='V'))) vmode = Parameter('control mode', EnumType(both_grounded=0, A=1, B=2, A_B_diff=3), readonly=False) range = Parameter('sensitivity value', FloatRange(0.00, 1), unit='V', default=1) autosen_on = Parameter('is auto sensitivity on', BoolType(), readonly=False) noise_control = Parameter('is noise control mode on', BoolType(), readonly=False) phase = Parameter('reference phase control', FloatRange(-360, 360), unit='deg', readonly=False) frequency = Parameter('oscill. frequen. control', FloatRange(0.001, 250e3), unit='Hz', readonly=False, group='frequency') amplitude = Parameter('oscill. amplit. control', FloatRange(0.00, 5), unit='V_rms', readonly=False) #filter = Parameter('line frequency filter', unit='Hz') sen_range = {name: value + 1 for value, name in enumerate( ['2nV', '5nV', '10nV', '20nV', '50nV', '100nV', '200nV', '500nV', '1uV', '2uV', '5uV', '10uV', '20uV', '50uV', '100uV', '200uV', '500uV', '1mV', '2mV', '5mV', '10mV', '20mV', '50mV', '100mV', '200mV', '500mV', '1V'] )} irange = Parameter('sensitivity index', EnumType('sensitivity index range', sen_range), readonly=False) time_const = {name: value for value, name in enumerate( ['10us', '20us', '50us', '100us', '200us', '500us', '1ms', '2ms', '5ms', '10ms', '20ms', '50ms', '100ms', '200ms', '500ms', '1s', '2s', '5s', '10s', '20s', '50s', '100s', '200s', '500s', '1ks', '10ks', '20ks', '50ks', '100ks'] )} tc = Parameter('time const. value', FloatRange(0.00005, 100000), unit='s', readonly=False) itc = Parameter('time const. index', EnumType('time const. index range', time_const), readonly=False) ioClass = SR_IO def comparison(self, curr_value, new_value, value_dict): c_ind = None # closest index c_diff = None # closets difference for index, value in value_dict.items(): if c_diff is None or diff < c_diff: c_ind = index c_diff = c_diff if abs(curr_value - new_value) < c_diff: return c_ind else: for index, value in value_dict.items(): diff = abs(new_value - value) if c_diff is None or diff < c_diff: c_ind = index c_diff = diff return c_ind def comm(self, cmd): reply, status, overload = self.communicate(cmd).split(';') if overload != '0': self.status = (self.Status.WARN, f'overload {overload}') self.status = (self.Status.IDLE, '') return reply def read_vmode(self): return self.comm('VMODE') def write_vmode(self, vmode): self.comm(f'IMODE {0}') return self.comm(f'VMODE {vmode}') def read_autosen_on(self): return self.comm('AUTOMATIC') def write_autosen_on(self, autosen_on): return self.comm(f'AUTOMATIC {autosen_on}') def read_irange(self): return self.comm('SEN') def write_irange(self, irange): self.comm(f'IMODE {0}') self.comm(f'SEN {irange}') self.read_range() return irange def read_range(self): return self.comm('SEN.') # range value def write_range(self): self.comm(f'IMODE 0') curr_value = self.read_range() new_value = self.value c_ind = self.comparison(curr_value, new_value, self.sen_range) return self.comm(f'SEN {c_ind}') def read_noise_control(self): return self.comm('NOISEMODE') def write_noise_control(self, noise_control): return self.comm(f'NOISEMODE {noise_control}') def read_tc(self): return self.comm('TC.') def write_tc(self): pass def read_itc(self): return self.comm('TC') def write_itc(self, new_itc): curr_value = self.read_itc() new_value = self.time_const[self.itc] c_ind = self.comparison(curr_value, new_value, self.time_const) if abs(curr_value - new_value) < c_diff: if self.read_noise_control() == 1 and (5e-4 <= self.time_const[new_itc] <= 1e-2): raise RangeError('not allowed with noisemode=1') return self.comm(f'TC {new_itc}') def read_value(self): reply = self.comm('XY.').split(b',') x = float(reply[0]) y = float(reply[1]) return x, y def write_value(self, value): return self.comm(f'XY {value}') def read_frequency(self): return self.comm('OF.') def write_frequency(self, frequency): frequency = self.frequency return self.comm(f'OF. {frequency}') def read_amplitude(self): return self.comm('OA.') def write_amplitude(self, amplitude): return self.comm(f'OA. {amplitude}') # phase and autophase def read_phase(self): return self.comm('REFP.') def write_phase(self, value): self.comm(f'REFP {round(1000 * value)}') return self.read_phase() def aphase(self): """auto phase""" self.read_phase() return self.comm('AQN')