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frappy/secop_psi/ppms.py
Markus Zolliker fcad78a682 ppms driver now uses command handlers 
this is a simplicifcation for the ppms driver

- the derivation of a changecmd from a querycmd is moved to
  CmdHandler.__init__
- the special treatment of handlers when writing configured
  parameters has moved to CmdHandler.write
- introduced Drivable.isDriving, changed Module.isBusy

Change-Id: I8862ecda9c8cc998bb018bd960f31c9488146707
Reviewed-on: https://forge.frm2.tum.de/review/c/sine2020/secop/playground/+/22033
Tested-by: JenkinsCodeReview <bjoern_pedersen@frm2.tum.de>
Reviewed-by: Markus Zolliker <markus.zolliker@psi.ch>
2019-12-13 17:13:41 +01:00

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#!/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:
# Markus Zolliker <markus.zolliker@psi.ch>
# *****************************************************************************
"""PPMS driver
The PPMS hardware has some special requirements:
- the communication to the hardware happens through windows COM
- all measured data including state are handled by one request/reply pair GETDAT?<mask>
- for each channel, the settings are handled through a single request/reply pair,
needing a mechanism to treat a single parameter change correctly.
Polling of value and status is done commonly for all modules. For each registered module
<module>.update_value_status() is called in order to update their value and status.
Polling of module settings is using the same poller (secop.Poller is checking iodev).
Only the hidden (not exported) parameter 'settings' is polled, all the others are updated
by read_settings. The modules parameters related to the settings are updated only on change.
This allows for example for the field module to buffer ramp and approachmode until the
next target or persistent_mode change happens, because sending the common command for
settings and target would do a useless cycle of ramping up leads, heating switch etc.
"""
import time
import threading
from secop.modules import Module, Readable, Drivable, Parameter, Override,\
Communicator, Property, Attached
from secop.datatypes import EnumType, FloatRange, IntRange, StringType,\
BoolType, StatusType
from secop.lib.enum import Enum
from secop.errors import HardwareError
from secop.poller import Poller
import secop.commandhandler
from secop.stringio import HasIodev
from secop.metaclass import Done
try:
import secop_psi.ppmswindows as ppmshw
except ImportError:
import secop_psi.ppmssim as ppmshw
class CmdHandler(secop.commandhandler.CmdHandler):
CMDARGS = ['no']
CMDSEPARATOR = None # no command chaining
READ_BEFORE_WRITE = False
def __init__(self, name, querycmd, replyfmt):
changecmd = querycmd.split('?')[0] + ' '
super().__init__(name, querycmd, replyfmt, changecmd)
class Main(Communicator):
"""general ppms dummy module"""
parameters = {
'pollinterval': Parameter('poll interval', readonly=False,
datatype=FloatRange(), default=2),
'communicate': Override('GBIP command'),
'data': Parameter('internal', poll=True, export=True, # export for test only
default="", readonly=True, datatype=StringType()),
}
properties = {
'class_id': Property('Quantum Design class id', export=False,
datatype=StringType()),
}
_channel_names = ['packed_status', 'temp', 'field', 'position', 'r1', 'i1', 'r2', 'i2',
'r3', 'i3', 'r4', 'i4', 'v1', 'v2', 'digital', 'cur1', 'pow1', 'cur2', 'pow2',
'p', 'u20', 'u21', 'u22', 'ts', 'u24', 'u25', 'u26', 'u27', 'u28', 'u29']
assert len(_channel_names) == 30
_channel_to_index = dict(((channel, i) for i, channel in enumerate(_channel_names)))
_status_bitpos = {'temp': 0, 'field': 4, 'chamber': 8, 'position': 12}
pollerClass = Poller
def earlyInit(self):
self.modules = {}
self._ppms_device = ppmshw.QDevice(self.class_id)
self.lock = threading.Lock()
def register(self, other):
self.modules[other.channel] = other
def do_communicate(self, command):
with self.lock:
reply = self._ppms_device.send(command)
self.log.debug("%s|%s", command, reply)
return reply
def read_data(self):
mask = 1 # always get packed_status
for channelname, channel in self.modules.items():
if channel.enabled:
mask |= 1 << self._channel_to_index.get(channelname, 0)
# send, read and convert to floats and ints
data = self.do_communicate('GETDAT? %d' % mask)
reply = data.split(',')
mask = int(reply.pop(0))
reply.pop(0) # pop timestamp
result = {}
for bitpos, channelname in enumerate(self._channel_names):
if mask & (1 << bitpos):
result[channelname] = float(reply.pop(0))
if 'temp' in result:
result['tv'] = result['temp']
if 'ts' in result:
result['temp'] = result['ts']
packed_status = int(result['packed_status'])
result['chamber'] = None # 'chamber' must be in result for status, but value is ignored
for channelname, channel in self.modules.items():
channel.update_value_status(result.get(channelname, None), packed_status)
return data # return data as string
class PpmsMixin(HasIodev, Module):
properties = {
'iodev': Attached(),
}
pollerClass = Poller
enabled = True # default, if no parameter enable is defined
# STATUS_MAP = {} # a mapping converting ppms status codes into SECoP status values
_last_target_change = 0 # used by several modules
_last_settings = None # used by several modules
slow_pollfactor = 1
def initModule(self):
self._iodev.register(self)
def startModule(self, started_callback):
# no polls except on main module
started_callback()
def read_value(self):
"""effective polling is done by the main module"""
if not self.enabled:
return Done
if self.parameters['value'].timestamp == 0:
# make sure that the value is read at least after init
self._iodev.read_data()
return self.value
def read_status(self):
"""effective polling is done by the main module"""
if not self.enabled:
return Done
if self.parameters['value'].timestamp == 0:
# make sure that the value is read at least after init
self._iodev.read_data()
return self.status
def update_value_status(self, value, packed_status):
"""update value and status
to be reimplemented for modules looking at packed_status
"""
if not self.enabled:
self.status = [self.Status.DISABLED, 'disabled']
return
if value is None:
self.status = [self.Status.ERROR, 'invalid value']
else:
self.value = value
self.status = [self.Status.IDLE, '']
class Channel(PpmsMixin, Readable):
parameters = {
'value':
Override('main value of channels', poll=True),
'enabled':
Parameter('is this channel used?', readonly=False, poll=False,
datatype=BoolType(), default=False),
'pollinterval':
Override(visibility=3),
}
properties = {
'channel':
Property('channel name',
datatype=StringType(), export=False, default=''),
'no':
Property('channel number',
datatype=IntRange(1, 4), export=False),
}
def earlyInit(self):
Readable.earlyInit(self)
if not self.channel:
self.properties['channel'] = self.name
def get_settings(self, pname):
return ''
class UserChannel(Channel):
parameters = {
'pollinterval':
Override(visibility=3),
}
properties = {
'no':
Property('channel number',
datatype=IntRange(0, 0), export=False, default=0),
}
class DriverChannel(Channel):
drvout = CmdHandler('drvout', 'DRVOUT? %(no)d', '%d,%g,%g')
parameters = {
'current':
Parameter('driver current', readonly=False, handler=drvout,
datatype=FloatRange(0., 5000., unit='uA')),
'powerlimit':
Parameter('power limit', readonly=False, handler=drvout,
datatype=FloatRange(0., 1000., unit='uW')),
'pollinterval':
Override(visibility=3),
}
def analyze_drvout(self, no, current, powerlimit):
if self.no != no:
raise HardwareError('DRVOUT command: channel number in reply does not match')
self.current = current
self.powerlimit = powerlimit
def change_drvout(self, new):
return new.current, new.powerlimit
class BridgeChannel(Channel):
bridge = CmdHandler('bridge', 'BRIDGE? %(no)d', '%d,%g,%g,%d,%d,%g')
# pylint: disable=invalid-name
ReadingMode = Enum('ReadingMode', standard=0, fast=1, highres=2)
parameters = {
'enabled':
Override(handler=bridge),
'excitation':
Parameter('excitation current', readonly=False, handler=bridge,
datatype=FloatRange(0.01, 5000., unit='uA')),
'powerlimit':
Parameter('power limit', readonly=False, handler=bridge,
datatype=FloatRange(0.001, 1000., unit='uW')),
'dcflag':
Parameter('True when excitation is DC (else AC)', readonly=False, handler=bridge,
datatype=BoolType()),
'readingmode':
Parameter('reading mode', readonly=False, handler=bridge,
datatype=EnumType(ReadingMode)),
'voltagelimit':
Parameter('voltage limit', readonly=False, handler=bridge,
datatype=FloatRange(0.0001, 100., unit='mV')),
'pollinterval':
Override(visibility=3),
}
_settingnames = ['no', 'excitation', 'powerlimit', 'dcflag', 'readingmode', 'voltagelimit']
def analyze_bridge(self, no, excitation, powerlimit, dcflag, readingmode, voltagelimit):
if self.no != no:
raise HardwareError('DRVOUT command: channel number in reply does not match')
self.enabled = excitation != 0 and powerlimit != 0 and voltagelimit != 0
self.excitation = excitation or self.excitation
self.powerlimit = powerlimit or self.powerlimit
self.dcflag = dcflag
self.readingmode = readingmode
self.voltagelimit = voltagelimit or self.voltagelimit
def change_bridge(self, new):
if new.enabled:
return self.no, new.excitation, new.powerlimit, new.dcflag, new.readingmode, new.voltagelimit
return self.no, 0, 0, new.dcflag, new.readingmode, 0
class Level(PpmsMixin, Readable):
"""helium level"""
level = CmdHandler('level', 'LEVEL?', '%g,%d')
parameters = {
'value': Override(datatype=FloatRange(unit='%'), handler=level),
'status': Override(handler=level),
'pollinterval':
Override(visibility=3),
}
channel = 'level'
def update_value_status(self, value, packed_status):
"""must be a no-op
when called from Main.read_data, value is always None
value and status is polled via settings
"""
def analyze_level(self, level, status):
if status:
self.status = [self.Status.IDLE, '']
else:
self.status = [self.Status.ERROR, 'old reading']
self.value = level
class Chamber(PpmsMixin, Drivable):
"""sample chamber handling
value is an Enum, which is redundant with the status text
"""
chamber = CmdHandler('chamber', 'CHAMBER?', '%d')
Status = Drivable.Status
# pylint: disable=invalid-name
Operation = Enum(
'Operation',
seal_immediately=0,
purge_and_seal=1,
vent_and_seal=2,
pump_continuously=3,
vent_continuously=4,
hi_vacuum=5,
noop=10,
)
StatusCode = Enum(
'StatusCode',
unknown=0,
purged_and_sealed=1,
vented_and_sealed=2,
sealed_unknown=3,
purge_and_seal=4,
vent_and_seal=5,
pumping_down=6,
at_hi_vacuum=7,
pumping_continuously=8,
venting_continuously=9,
general_failure=15,
)
parameters = {
'value':
Override(description='chamber state', handler=chamber,
datatype=EnumType(StatusCode)),
'target':
Override(description='chamber command', handler=chamber,
datatype=EnumType(Operation)),
'pollinterval':
Override(visibility=3),
}
STATUS_MAP = {
StatusCode.unknown: [Status.WARN, 'unknown'],
StatusCode.purged_and_sealed: [Status.IDLE, 'purged and sealed'],
StatusCode.vented_and_sealed: [Status.IDLE, 'vented and sealed'],
StatusCode.sealed_unknown: [Status.WARN, 'sealed unknown'],
StatusCode.purge_and_seal: [Status.BUSY, 'purge and seal'],
StatusCode.vent_and_seal: [Status.BUSY, 'vent and seal'],
StatusCode.pumping_down: [Status.BUSY, 'pumping down'],
StatusCode.at_hi_vacuum: [Status.IDLE, 'at hi vacuum'],
StatusCode.pumping_continuously: [Status.IDLE, 'pumping continuously'],
StatusCode.venting_continuously: [Status.IDLE, 'venting continuously'],
StatusCode.general_failure: [Status.ERROR, 'general failure'],
}
channel = 'chamber'
_settingnames = ['target']
def update_value_status(self, value, packed_status):
"""update value and status"""
self.value = (packed_status >> 8) & 0xf
self.status = self.STATUS_MAP[self.value]
def analyze_chamber(self, target):
self.target = target
def change_chamber(self, new):
"""write settings, combining <pname>=<value> and current attributes
and request updated settings
"""
if new.target == self.Operation.noop:
return None
return (new.target,)
class Temp(PpmsMixin, Drivable):
"""temperature"""
temp = CmdHandler('temp', 'TEMP?', '%g,%g,%d')
Status = Enum(Drivable.Status,
RAMPING = 370,
STABILIZING = 380,
)
# pylint: disable=invalid-name
ApproachMode = Enum('ApproachMode', fast_settle=0, no_overshoot=1)
parameters = {
'value':
Override(datatype=FloatRange(unit='K'), poll=True),
'status':
Override(datatype=StatusType(Status), poll=True),
'target':
Override(datatype=FloatRange(1.7, 402.0, unit='K'), handler=temp),
'ramp':
Parameter('ramping speed', readonly=False, handler=temp,
datatype=FloatRange(0, 20, unit='K/min')),
'approachmode':
Parameter('how to approach target!', readonly=False, handler=temp,
datatype=EnumType(ApproachMode)),
'pollinterval':
Override(visibility=3),
'timeout':
Parameter('drive timeout, in addition to ramp time', readonly=False,
datatype=FloatRange(0, unit='sec'), default=3600),
}
properties = {
'general_stop': Property('respect general stop', datatype=BoolType(),
export=True, default=True)
}
# pylint: disable=invalid-name
TempStatus = Enum(
'TempStatus',
unknown=0,
stable_at_target=1,
changing=2,
within_tolerance=5,
outside_tolerance=6,
standby=10,
control_disabled=13,
can_not_complete=14,
general_failure=15,
)
STATUS_MAP = {
0: [Status.ERROR, 'unknown'],
1: [Status.IDLE, 'stable at target'],
2: [Status.RAMPING, 'changing'],
5: [Status.STABILIZING, 'within tolerance'],
6: [Status.STABILIZING, 'outside tolerance'],
10: [Status.WARN, 'standby'],
13: [Status.WARN, 'control disabled'],
14: [Status.ERROR, 'can not complete'],
15: [Status.ERROR, 'general failure'],
}
channel = 'temp'
_settingnames = ['target', 'ramp', 'approachmode']
_stopped = False
_expected_target = 0
_last_change = 0 # 0 means no target change is pending
def earlyInit(self):
self.setProperty('general_stop', False)
super().earlyInit()
def update_value_status(self, value, packed_status):
"""update value and status"""
if value is None:
self.status = [self.Status.ERROR, 'invalid value']
return
self.value = value
status = self.STATUS_MAP[packed_status & 0xf]
now = time.time()
if self._stopped:
# combine 'stopped' with current status text
if status[0] == self.Status.IDLE:
self._stopped = False
else:
self.status = [self.Status.IDLE, 'stopped(%s)' % status[1]]
return
if self._last_change: # there was a change, which is not yet confirmed by hw
if self.isDriving(status):
if now > self._last_change + 15 or status != self._status_before_change:
self._last_change = 0
self.log.debug('time needed to change to busy: %.3g', now - self._last_change)
else:
if now < self._last_change + 15:
status = [self.Status.BUSY, 'changed target while %s' % status[1]]
else:
status = [self.Status.WARN, 'temperature status (%r) does not change to BUSY' % status]
if self._expected_target:
# handle timeout
if self.isDriving(status):
if now > self._expected_target + self.timeout:
status = [self.Status.WARN, 'timeout while %s' % status[1]]
else:
self._expected_target = 0
self.status = status
def analyze_temp(self, target, ramp, approachmode):
if (target, ramp, approachmode) != self._last_settings:
# we update parameters only on change, as 'approachmode'
# is not always sent to the hardware
self._last_settings = target, ramp, approachmode
self.target = target
self.ramp =ramp
self.approachmode = approachmode
def change_temp(self, new):
self.calc_expected(new.target, self.ramp)
return new.target, new.ramp, new.approachmode
def write_target(self, target):
self._stopped = False
if abs(self.target - self.value) < 2e-5 and target == self.target:
return None
self._status_before_change = self.status
self.status = [self.Status.BUSY, 'changed_target']
self._last_change = time.time()
return target
def write_approachmode(self, value):
if self.isDriving():
return value
return None # change_temp will not be called, as this would trigger an unnecessary T change
def write_ramp(self, value):
if self.isDriving():
return value
return None # change_temp will not be called, as this would trigger an unnecessary T change
def calc_expected(self, target, ramp):
self._expected_target = time.time() + abs(target - self.value) * 60.0 / max(0.1, ramp)
def do_stop(self):
if self.isDriving():
return
if self.status[0] == self.Status.STABILIZING:
# we are already near target
newtarget = self.target
else:
newtarget = self.value
self.log.info('stop at %s K', newtarget)
self.write_target(newtarget)
self.status = [self.Status.IDLE, 'stopped']
self._stopped = True
class Field(PpmsMixin, Drivable):
"""magnetic field"""
field = CmdHandler('field', 'FIELD?', '%g,%g,%d,%d')
Status = Enum(Drivable.Status,
PREPARED = 150,
PREPARING = 340,
RAMPING = 370,
FINALIZING = 390,
)
# pylint: disable=invalid-name
PersistentMode = Enum('PersistentMode', persistent = 0, driven = 1)
ApproachMode = Enum('ApproachMode', linear=0, no_overshoot=1, oscillate=2)
parameters = {
'value':
Override(datatype=FloatRange(unit='T'), poll=True),
'status':
Override(datatype=StatusType(Status), poll=True),
'target':
Override(datatype=FloatRange(-15,15,unit='T'), handler=field),
'ramp':
Parameter('ramping speed', readonly=False, handler=field,
datatype=FloatRange(0.064, 1.19, unit='T/min')),
'approachmode':
Parameter('how to approach target', readonly=False, handler=field,
datatype=EnumType(ApproachMode)),
'persistentmode':
Parameter('what to do after changing field', readonly=False, handler=field,
datatype=EnumType(PersistentMode)),
'pollinterval':
Override(visibility=3),
}
STATUS_MAP = {
0: [Status.ERROR, 'unknown'],
1: [Status.IDLE, 'persistent mode'],
2: [Status.PREPARING, 'switch warming'],
3: [Status.FINALIZING, 'switch cooling'],
4: [Status.IDLE, 'driven stable'],
5: [Status.FINALIZING, 'driven final'],
6: [Status.RAMPING, 'charging'],
7: [Status.RAMPING, 'discharging'],
8: [Status.ERROR, 'current error'],
15: [Status.ERROR, 'general failure'],
}
channel = 'field'
_stopped = False
_last_target = 0
_last_change= 0 # means no target change is pending
def update_value_status(self, value, packed_status):
"""update value and status"""
if value is None:
self.status = [self.Status.ERROR, 'invalid value']
return
self.value = round(value * 1e-4, 7)
status_code = (packed_status >> 4) & 0xf
status = self.STATUS_MAP[status_code]
now = time.time()
if self._stopped:
# combine 'stopped' with current status text
if status[0] == self.Status.IDLE:
self._stopped = False
else:
self.status = [status[0], 'stopped (%s)' % status[1]]
return
elif self._last_change: # there was a change, which is not yet confirmed by hw
if status_code == 1: # persistent mode
# leads are ramping (ppms has no extra status code for this!)
if now < self._last_change + 30:
status = [self.Status.PREPARING, 'ramping leads']
else:
status = [self.Status.WARN, 'timeout when ramping leads']
elif self.isDriving(status):
if now > self._last_change + 5 or status != self._status_before_change:
self._last_change = 0
self.log.debug('time needed to change to busy: %.3g', now - self._last_change)
else:
if now < self._last_change + 5:
status = [self.Status.BUSY, 'changed target while %s' % status[1]]
else:
status = [self.Status.WARN, 'field status (%r) does not change to BUSY' % status]
self.status = status
def analyze_field(self, target, ramp, approachmode, persistentmode):
if (target, ramp, approachmode, persistentmode) != self._last_settings:
# we update parameters only on change, as 'ramp' and 'approachmode' are
# not always sent to the hardware
self._last_settings = target, ramp, approachmode, persistentmode
self.target = target * 1e-4
self.ramp = ramp * 6e-3
self.approachmode = approachmode
self.persistentmode = persistentmode
def change_field(self, new):
if 'target' in new or 'persistentmode' in new:
# changed target or persistentmode
if 'target' in new:
self._last_target = self.target # save for stop command
self._stopped = False
self._last_change = time.time()
self._status_before_change = list(self.status)
else:
# changed ramp or approachmode
if not self.isDriving():
return None # nothing to be written, as this would trigger a ramp up of leads current
return new.target * 1e+4, new.ramp / 6e-3, new.approachmode, new.persistentmode
def do_stop(self):
if not self.isDriving():
return
self.status = [self.Status.IDLE, '_stopped']
self._stopped = True
if abs(self.value - self.target) > 1e-4:
# ramping is not yet at end
if abs(self.value - self._last_target) < 1e-4:
# ramping has not started yet, use more precise last target instead of current value
self.target = self.put_settings(self._last_target, 'target')
else:
self.target = self.put_settings(self.value, 'target')
class Position(PpmsMixin, Drivable):
"""rotator position"""
move = CmdHandler('move', 'MOVE?', '%g,%g,%g')
Status = Drivable.Status
parameters = {
'value':
Override(datatype=FloatRange(unit='deg'), poll=True),
'target':
Override(datatype=FloatRange(-720., 720., unit='deg'), handler=move),
'enabled':
Parameter('is this channel used?', readonly=False, poll=False,
datatype=BoolType(), default=True),
'speed':
Parameter('motor speed', readonly=False, handler=move,
datatype=FloatRange(0.8, 12, unit='deg/sec')),
'pollinterval':
Override(visibility=3),
}
STATUS_MAP = {
0: [Status.ERROR, 'unknown'],
1: [Status.IDLE, 'at target'],
5: [Status.BUSY, 'moving'],
8: [Status.IDLE, 'at limit'],
9: [Status.IDLE, 'at index'],
15: [Status.ERROR, 'general failure'],
}
channel = 'position'
_settingnames = ['target', 'mode', 'speed']
_stopped = False
_last_target = 0
_last_change = 0 # means no target change is pending
def update_value_status(self, value, packed_status):
"""update value and status"""
if not self.enabled:
self.status = [self.Status.DISABLED, 'disabled']
return
if value is None:
self.status = [self.Status.ERROR, 'invalid value']
return
self.value = value
status = self.STATUS_MAP[(packed_status >> 12) & 0xf]
if self._stopped:
# combine 'stopped' with current status text
if status[0] == self.Status.IDLE:
self._stopped = False
else:
status = [self.Status.IDLE, 'stopped(%s)' % status[1]]
if self._last_change: # there was a change, which is not yet confirmed by hw
now = time.time()
if self.isDriving():
if now > self._last_change + 15 or status != self._status_before_change:
self._last_change = 0
self.log.debug('time needed to change to busy: %.3g', now - self._last_change)
else:
if now < self._last_change + 15:
status = [self.Status.BUSY, 'changed target while %s' % status[1]]
else:
status = [self.Status.WARN, 'temperature status (%r) does not change to BUSY' % status]
self.status = status
def analyze_move(self, target, mode, speed):
if (target, speed) != self._last_settings:
# we update parameters only on change, as 'speed' is
# not always sent to the hardware
self._last_settings = target, speed
self.target = target
self.speed = (15 - speed) * 0.8
def change_move(self, new):
speed = int(round(min(14, max(0, 15 - new.speed / 0.8)), 0))
return new.target, 0, speed
def write_target(self, target):
self._last_target = self.target # save for stop command
self._stopped = False
self._last_change = 0
self._status_before_change = self.status
return target
def write_speed(self, value):
if self.isDriving():
return value
return None # change_move not called: as this would trigger an unnecessary move
def do_stop(self):
if not self.isDriving():
return
self.status = [self.Status.BUSY, '_stopped']
self._stopped = True
if abs(self.value - self.target) > 1e-2:
# moving is not yet at end
if abs(self.value - self._last_target) < 1e-2:
# moving has not started yet, use more precise last target instead of current value
self.target = self.write_target(self._last_target)
else:
self.target = self.write_target(self.value)
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