def __init__(self, tty=None):
if tty is None:
tty = self.detect_tty()
if tty is None:
raise ValueError('Myo dongle not found!')
self.bt = BT(tty)
self.conn = None
self.emg_handlers = []
self.imu_handlers = []
self.arm_handlers = []
self.gesture_handlers = []
class MyoRaw(object):
'''Implements the Myo-specific communication protocol.'''
def __init__(self, tty=None):
if tty is None:
tty = self.detect_tty()
if tty is None:
raise ValueError('Myo dongle not found!')
self.bt = BT(tty)
self.conn = None
self.emg_handlers = []
self.imu_handlers = []
self.arm_handlers = []
self.gesture_handlers = []
def detect_tty(self):
for p in comports():
if re.search(r'PID=2458:0*1', p[2]):
print('using device:', p[0])
return p[0]
return None
def run(self, timeout=None):
self.bt.recv_packet(timeout)
def connect(self):
# stop everything from before
self.bt.end_scan()
self.bt.disconnect(0)
self.bt.disconnect(1)
self.bt.disconnect(2)
# start scanning
print('scanning...')
self.bt.discover()
while True:
p = self.bt.recv_packet()
print('scan response:', p)
if p.payload.endswith(b'\x06\x42\x48\x12\x4A\x7F\x2C\x48\x47\xB9\xDE\x04\xA9\x01\x00\x06\xD5'):
addr = list(multiord(p.payload[2:8]))
break
self.bt.end_scan()
# connect and wait for status event
conn_pkt = self.bt.connect(addr)
self.conn = multiord(conn_pkt.payload)[-1]
self.bt.wait_event(3, 0)
# get firmware version
fw = self.read_attr(0x17)
_, _, _, _, v0, v1, v2, v3 = unpack('BHBBHHHH', fw.payload)
print('firmware version: %d.%d.%d.%d' % (v0, v1, v2, v3))
self.old = (v0 == 0)
if self.old:
# don't know what these do
# Myo Connect sends them, though we get data
# fine without them
self.write_attr(0x19, b'\x01\x02\x00\x00')
self.write_attr(0x2f, b'\x01\x00')
self.write_attr(0x2c, b'\x01\x00')
self.write_attr(0x32, b'\x01\x00')
self.write_attr(0x35, b'\x01\x00')
# enable EMG data
self.write_attr(0x28, b'\x01\x00')
# enable IMU data
self.write_attr(0x1d, b'\x01\x00')
# Sampling rate of the underlying EMG sensor, capped to 1000.
# If it's less than 1000, emg_hz is correct. If it is greater,
# the actual framerate starts dropping inversely. Also, if this
# is much less than 1000, EMG data becomes slower to respond to
# changes. In conclusion, 1000 is probably a good value.
C = 1000
emg_hz = 50
# strength of low-pass filtering of EMG data
emg_smooth = 100
imu_hz = 50
# send sensor parameters, or we don't get any data
self.write_attr(0x19, pack('BBBBHBBBBB', 2, 9, 2, 1, C,
emg_smooth, C // emg_hz, imu_hz, 0, 0))
else:
name = self.read_attr(0x03)
print('device name: %s' % name.payload)
# enable IMU data
self.write_attr(0x1d, b'\x01\x00')
# enable on/off arm notifications
self.write_attr(0x24, b'\x02\x00')
self.start_raw()
# add data handlers
def handle_data(p):
if (p.cls, p.cmd) != (4, 5):
return
c, attr, typ = unpack('BHB', p.payload[:4])
pay = p.payload[5:]
if attr == 0x27:
vals = unpack('8HB', pay)
# not entirely sure what the last byte is,
# but it's a bitmask that seems to indicate which
# sensors think they're being moved around or something
emg = vals[:8]
moving = vals[8]
self.on_emg(emg, moving)
elif attr == 0x1c:
vals = unpack('10h', pay)
quat = vals[:4]
acc = vals[4:7]
gyro = vals[7:10]
self.on_imu(quat, acc, gyro)
elif attr == 0x23:
if len(pay) == 6:
try:
typ, val, xdir, _, _, _ = unpack('6B', pay)
except Exception as e:
print("Got exception: " + str(e) + "\nContinuing...")
return
elif len(pay) == 3:
try:
typ, val, xdir = unpack('3B', pay)
except Exception as e:
print("Got exception: " + str(e) + "\nContinuing...")
return
if typ == 1: # on arm
self.on_arm(MyoArm(arm=val, xdir=xdir))
elif typ == 2: # removed from arm
self.on_arm(MyoArm(MyoArm.UNKNOWN, MyoArm.UNKNOWN))
elif typ == 3: # gesture
if val == 255:
gesture = MyoGesture(0)
else:
gesture = MyoGesture(val + 1)
self.on_gesture(gesture)
else:
print('data with unknown attr: %02X %s' % (attr, p))
self.bt.add_handler(handle_data)
def write_attr(self, attr, val):
if self.conn is not None:
self.bt.write_attr(self.conn, attr, val)
def read_attr(self, attr):
if self.conn is not None:
return self.bt.read_attr(self.conn, attr)
return None
def disconnect(self):
if self.conn is not None:
self.bt.disconnect(self.conn)
def start_raw(self):
'''Sending this sequence for v1.0 firmware seems to enable both raw data and
pose notifications.
'''
self.write_attr(0x28, b'\x01\x00')
self.write_attr(0x19, b'\x01\x03\x01\x01\x01')
def mc_start_collection(self):
'''Myo Connect sends this sequence (or a reordering) when starting data
collection for v1.0 firmware; this enables raw data but disables arm
and pose notifications.'''
self.write_attr(0x28, b'\x01\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x24, b'\x02\x00')
self.write_attr(0x19, b'\x01\x03\x01\x01\x01')
self.write_attr(0x28, b'\x01\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x19, b'\x09\x01\x01\x00\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x19, b'\x01\x03\x00\x01\x00')
self.write_attr(0x28, b'\x01\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x19, b'\x01\x03\x01\x01\x00')
def mc_end_collection(self):
'''Myo Connect sends this sequence (or a reordering) when ending data
collection for v1.0 firmware; this reenables arm and pose
notifications, but doesn't disable raw data.'''
self.write_attr(0x28, b'\x01\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x24, b'\x02\x00')
self.write_attr(0x19, b'\x01\x03\x01\x01\x01')
self.write_attr(0x19, b'\x09\x01\x00\x00\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x24, b'\x02\x00')
self.write_attr(0x19, b'\x01\x03\x00\x01\x01')
self.write_attr(0x28, b'\x01\x00')
self.write_attr(0x1d, b'\x01\x00')
self.write_attr(0x24, b'\x02\x00')
self.write_attr(0x19, b'\x01\x03\x01\x01\x01')
def vibrate(self, length):
if length in xrange(1, 4):
# first byte tells it to vibrate; purpose of second byte is unknown
self.write_attr(0x19, pack('3B', 3, 1, length))
def add_emg_handler(self, h):
self.emg_handlers.append(h)
def add_imu_handler(self, h):
self.imu_handlers.append(h)
def add_gesture_handler(self, h):
self.gesture_handlers.append(h)
def add_arm_handler(self, h):
self.arm_handlers.append(h)
def on_emg(self, emg, moving):
for h in self.emg_handlers:
h(emg, moving)
def on_imu(self, quat, acc, gyro):
for h in self.imu_handlers:
h(quat, acc, gyro)
def on_gesture(self, p):
for h in self.gesture_handlers:
h(p)
def on_arm(self, myoarm_msg):
for h in self.arm_handlers:
h(myoarm_msg)