[Discuss-gnuradio] error using rx_voice.py

[pratik hetamsaria]

I am working on tx_voice.py and rx_voice.py and I am trying to embed a fixed sequence in the payload part of my packet. However, when i try to receive the data using rx_voice, i get an error saying 

terminate called after throwing an instance of 'std::runtime_error'
  what():  msg length is not a multiple of d_itemsize
Aborted (core dumped)

I have added only one line in make_packet in packet_utils.py  and it looks like this:(just the important lines as i thought)

def make_packet(payload, samples_per_symbol, bits_per_symbol,
                access_code=default_access_code, pad_for_usrp=True):

    (packed_access_code, padded) = conv_1_0_string_to_packed_binary_string(access_code)
    (packed_preamble, ignore) = conv_1_0_string_to_packed_binary_string(preamble)
    payload =
 packed_preamble + payload
    payload_with_crc = gru.gen_and_append_crc32(payload)
    pkt = ''.join((packed_access_code, make_header(L), whiten(payload_with_crc), '\x55'))
    
    if pad_for_usrp:
        pkt = pkt + (_npadding_bytes(len(pkt), samples_per_symbol, bits_per_symbol) * '\x55')

    return pkt


Can anyone please explain how to remove this error. I want to add fixed sequence so that it helps in calculation of BER.

Thanks,
Pratik Hetamsaria

---

Here’s a new way to find what you're looking for - Yahoo! Answers