import struct
import time
from bluetooth import *
import _bluetooth as bt

# check voice settings.  switch to S16 LE mono 8kHz CVSD if needed
hci_sock=bt.hci_open_dev()
response = bt.hci_send_req(hci_sock, bt.OGF_HOST_CTL, 
        bt.OCF_READ_VOICE_SETTING, bt.EVT_CMD_COMPLETE, 3)
status, voice_setting = struct.unpack("<BH", response)
if voice_setting != 0x60:
    new_vs = struct.pack("<H", 0x60)
    bt.hci_send_req(hci_sock, bt.OGF_HOST_CTL, 
            bt.OCF_WRITE_VOICE_SETTING, bt.EVT_CMD_COMPLETE, 1, new_vs)

# determine the maximum packet size
response = bt.hci_send_req(hci_sock, bt.OGF_INFO_PARAM, 
        bt.OCF_READ_BUFFER_SIZE, bt.EVT_CMD_COMPLETE, 8)
status, acl_mtu, sco_mtu, acl_nbufs, sco_nbufs = \
        struct.unpack("<BHBHH", response)

server_address = "01:23:45:67:89:AB"

sock=BluetoothSocket( SCO )
sock.connect((server_address,))

# send one second's worth of silence
tosend = "\0" * 16000
sent = 0
while sent < 16000:
    sent += sock.send(tosend[sent:sent+sco_mtu])
    print sent

time.sleep(2)

sock.close()