"""Driver for accessing the features of the SR560 pre-amp"""
from time import sleep
import serial
[docs]class SR560Driver:
"""Class for lower level access to the pre-amp settings"""
def __init__(self, serial_port):
self._serial_port = serial_port
self._set('LALL') # make pre-amp listen
[docs] def set_blanking(self, blanked):
"""Operates amplifier blanking"""
cmd = {
'not blanked': 'BLINK 0',
'blanked': 'BLINK 1'
}
try:
self._set(cmd[blanked])
except KeyError:
raise RuntimeError('Invalid blanking value: {}'.format(blanked))
[docs] def set_coupling(self, coupling):
"""Sets input coupling"""
cmd = {
'ground': 'CPLG0',
'DC': 'CPLG1',
'AC': 'CPLG2'
}
try:
self._set(cmd[coupling])
except KeyError:
raise RuntimeError('Invalid coupling value: {}'.format(coupling))
[docs] def set_reserve(self, dynamic_reserve):
"""Sets dynamic reserve"""
cmd = {
'low noise': 'DYNR 0',
'high DR': 'DYNR 1',
'calibration gains': 'DYNR 2'
}
try:
self._set(cmd[dynamic_reserve])
except KeyError:
raise RuntimeError('Invalid dynamic reserve value: {}'.format(dynamic_reserve))
[docs] def set_filter_mode(self, filter_mode):
"""Sets filter mode"""
cmd = {
'bypass': 'FLTM 0',
'6 dB low pass': 'FLTM 1',
'12 dB low pass': 'FLTM 2',
'6 dB high pass': 'FLTM 3',
'12 dB high pass': 'FLTM 4',
'bandpass': 'FLTM 5'
}
try:
self._set(cmd[filter_mode])
except KeyError:
raise RuntimeError('Invalid filter mode value: {}'.format(filter_mode))
[docs] def set_gain(self, gain):
"""Sets the gain"""
cmd = {
'1': 'GAIN 0',
'2': 'GAIN 1',
'5': 'GAIN 2',
'10': 'GAIN 3',
'20': 'GAIN 4',
'50': 'GAIN 5',
'100': 'GAIN 6',
'200': 'GAIN 7',
'500': 'GAIN 8',
'1 k': 'GAIN 9',
'2 k': 'GAIN 10',
'5 k': 'GAIN 11',
'10 k': 'GAIN 12',
'20 k': 'GAIN 13',
'50 k': 'GAIN 14'
}
try:
self._set(cmd[gain])
except KeyError:
raise RuntimeError('Invalid gain value: {}'.format(gain))
[docs] def set_highpass_filter(self, highpass_filter):
"""Sets highpass filter frequency"""
cmd = {
'0.03 Hz': 'HFRQ0',
'0.1 Hz': 'HFRQ1',
'0.3 Hz': 'HFRQ2',
'1 Hz': 'HFRQ3',
'3 Hz': 'HFRQ4',
'10 Hz': 'HFRQ5',
'30 Hz': 'HFRQ6',
'100 Hz': 'HFRQ7',
'300 Hz': 'HFRQ8',
'1 kHz': 'HFRQ9',
'3 kHz': 'HFRQ10',
'10 kHz': 'HFRQ11'
}
try:
self._set(cmd[highpass_filter])
except KeyError:
raise RuntimeError('Invalid highpass filter value: {}'.format(highpass_filter))
[docs] def set_lowpass_filter(self, lowpass_filter):
"""Sets the lowpass filter frequency"""
cmd = {
'0.03 Hz': 'LFRQ 0',
'0.1 Hz': 'LFRQ 1',
'0.3 Hz': 'LFRQ 2',
'1 Hz': 'LFRQ 3',
'3 Hz': 'LFRQ 4',
'10 Hz': 'LFRQ 5',
'30 Hz': 'LFRQ 6',
'100 Hz': 'LFRQ 7',
'300 Hz': 'LFRQ 8',
'1 kHz': 'LFRQ 9',
'3 kHz': 'LFRQ 10',
'10 kHz': 'LFRQ 11',
'30 kHz': 'LFRQ 12',
'100 kHz': 'LFRQ 13',
'300 kHz': 'LFRQ 14',
'1 MHz': 'LFRQ 15'
}
try:
self._set(cmd[lowpass_filter])
except KeyError:
raise RuntimeError('Invalid lowpass filter value: {}'.format(lowpass_filter))
[docs] def set_signal_invert_sense(self, signal_invert_sense):
"""Sets the signal invert sense"""
cmd = {
'non-inverted': 'INVT 0',
'inverted': 'INVT 1'
}
try:
self._set(cmd[signal_invert_sense])
except KeyError:
raise RuntimeError(
'Invalid signal invert sense value: {}'.format(signal_invert_sense))
[docs] def set_vernier_gain_status(self, vernier_gain_status):
"""Sets the vernier gain status"""
cmd = {
"calibrated gain": 'UCAL 0',
'vernier gain': 'UCAL 1'
}
try:
self._set(cmd[vernier_gain_status])
except KeyError:
raise RuntimeError(
'Invalid vernier gain status value: {}'.format(vernier_gain_status))
[docs] def set_vernier_gain(self, vernier_gain):
"""Sets to vernier gain"""
self._set('UCGN {}'.format(vernier_gain))
[docs] def set_defaults(self):
"""Set all default settings"""
self._set('*RST')
def _set(self, cmd):
"""Sets a value on the pre-amp
:param cmd: the command to send to the pre-amp
:type cmd: str
"""
with serial.Serial(self._serial_port,
baudrate=9600,
bytesize=serial.EIGHTBITS,
parity=serial.PARITY_NONE,
stopbits=serial.STOPBITS_TWO) as connection:
connection.write((cmd + '\r\n').encode('ascii'))
sleep(0.1)
