66   def __init__(self, device=None, serialno=None, wait=1):  argument
75     self._coarse_ref = self._fine_ref = self._coarse_zero = self._fine_zero = 0
76     self._coarse_scale = self._fine_scale = 0
77     self._last_seq = 0
78     self.start_voltage = 0
81       self.ser = serial.Serial(device, timeout=1)
88         self._tempfile = open(tmpname, "w")
94           fcntl.lockf(self._tempfile, fcntl.LOCK_EX | fcntl.LOCK_NB)
100           self.ser = serial.Serial("/dev/%s" % dev, timeout=1)
101           self.StopDataCollection()  # just in case
102           self._FlushInput()  # discard stale input
103           status = self.GetStatus()
114           self.start_voltage = status["voltage1"]
117       self._tempfile = None
123   def GetStatus(self):  argument
144     self._SendStruct("BBB", 0x01, 0x00, 0x00)
146       bytes = self._ReadPacket()
171   def RampVoltage(self, start, end):  argument
175       self.SetVoltage(v)
178     self.SetVoltage(end)
180   def SetVoltage(self, v):  argument
183       self._SendStruct("BBB", 0x01, 0x01, 0x00)
185       self._SendStruct("BBB", 0x01, 0x01, int((v - 2.0) * 100))
188   def SetMaxCurrent(self, i):  argument
193     self._SendStruct("BBB", 0x01, 0x0a, val & 0xff)
194     self._SendStruct("BBB", 0x01, 0x0b, val >> 8)
196   def SetUsbPassthrough(self, val):  argument
198     self._SendStruct("BBB", 0x01, 0x10, val)
201   def StartDataCollection(self):  argument
203     self._SendStruct("BBB", 0x01, 0x1b, 0x01) # Mystery command
204     self._SendStruct("BBBBBBB", 0x02, 0xff, 0xff, 0xff, 0xff, 0x03, 0xe8)
207   def StopDataCollection(self):  argument
209     self._SendStruct("BB", 0x03, 0x00) # stop
212   def CollectData(self):  argument
215       bytes = self._ReadPacket()
226       if self._last_seq and seq & 0xF != (self._last_seq + 1) & 0xF:
228       self._last_seq = seq
231         if not self._coarse_scale or not self._fine_scale:
238             out.append(((main & ~1) - self._coarse_zero) * self._coarse_scale)
240             out.append((main - self._fine_zero) * self._fine_scale)
244         self._fine_zero = data[0][0]
245         self._coarse_zero = data[1][0]
250         self._fine_ref = data[0][0]
251         self._coarse_ref = data[1][0]
259       if self._coarse_ref != self._coarse_zero:
260         self._coarse_scale = 2.88 / (self._coarse_ref - self._coarse_zero)
261       if self._fine_ref != self._fine_zero:
262         self._fine_scale = 0.0332 / (self._fine_ref - self._fine_zero)
265   def _SendStruct(self, fmt, *args):  argument
271     self.ser.write(out)
274   def _ReadPacket(self):  argument
276     len_char = self.ser.read(1)
285     result = self.ser.read(data_len)
294   def _FlushInput(self):  argument
296     self.ser.flush()
299       ready_r, ready_w, ready_x = select.select([self.ser], [], [self.ser], 0)
305         self.ser.read(1)  # This may cause underlying buffering.
306         self.ser.flush()  # Flush the underlying buffer too.