def _extract(self, data):
"""
Extract the data portion from the response
"""
checksum = data[-3:]
calc_checksum = Protocol._checksum(data[:-3])
if checksum != calc_checksum:
raise exceptions.InstrumentDataException('Invalid checksum on %s, calculated %s' % (data, calc_checksum))
return int(data[-9:-3])
def _generic_response_handler(self, resp, prompt):
"""
Parse the response from the turbopump.
@param resp: response
@param prompt: unused, require to match signature
@returns: integer value extracted from response
@throws InstrumentDataException
"""
my_checksum = self._checksum(resp[:-3])
if resp[-3:] != my_checksum:
err_str = 'bad checksum: %r calculated: %r' % (resp, my_checksum)
raise exceptions.InstrumentDataException(err_str)
command = int(resp[5:8])
data_length = int(resp[8:10])
data = resp[10:-3]
log.trace('command: %s data: %s', command, data)
if len(data) != data_length:
raise exceptions.InstrumentDataException('invalid data length: %r' % resp)
if command not in InstrumentCommand.list():
raise exceptions.InstrumentDataException('command not found: %r' % resp)
return int(data)