OK, sadly that means I'm even more confused :(
packet_decoder doesn't have any CRC checking!

Best regards,
Marcus

On 21.02.2016 14:20, SangHyuk Kim wrote:
> No! I'm using current version. the link was just for showing.!
>
> 2016-02-21 22:14 GMT+09:00 Marcus Müller <[email protected]
> <mailto:[email protected]>>:
>
>     Hi,
>
>     thanks! Now it's clear what you're using :)
>     Is there a reason why you used a link to an outdated version of
>     the file from 2011?
>
>     Best regards,
>     Marcus
>
>
>     On 21.02.2016 14:02, SangHyuk Kim wrote:
>>     I'm using "packet_decoder" (http://goo.gl/7uVDDa)
>>
>>
>>
>>     2016-02-21 21:51 GMT+09:00 Marcus Müller
>>     <[email protected] <mailto:[email protected]>>:
>>
>>         Hi,
>>
>>         the problem is that the string "packet decoding" doesn't
>>         appear anywhere in the current GNU Radio source code, so I'm
>>         still not sure which block you are using. Also,
>>         crc.check_crc32 is used in two different blocks, so I can't
>>         even tell this way what we are talking about :(
>>         Can you actually make sure twice you got the
>>         letter-for-letter right name of the "packet decoding" block?
>>
>>         Best regards,
>>         marcis
>>
>>
>>
>>         On 21.02.2016 13:38, SangHyuk Kim wrote:
>>>         Thank Marcus.
>>>
>>>         "packet decoding" recovers message from received packet 
>>>
>>>         and i got false from crc.py
>>>
>>>         def check_crc32(s):
>>>             if len(s) < 4:
>>>                 return (False, '')
>>>             msg = s[:-4]
>>>             #print "msg = '%s'" % (msg,)
>>>             actual = digital.crc32(msg)
>>>             (expected,) = struct.unpack(">I", s[-4:])
>>>             #print "actual =", hex(actual), "expected =", hex(expected)
>>>            /*print actual == expected*/
>>>             return (actual == expected, msg)
>>>
>>>         2016-02-21 20:52 GMT+09:00 Marcus Müller
>>>         <[email protected] <mailto:[email protected]>>:
>>>
>>>             Dear Sang Hyuk Kim,
>>>
>>>             what "packet decoding" are you specifically talking
>>>             about, and could you show us the code you've modified?
>>>
>>>             Best regards,
>>>             Marcus
>>>
>>>
>>>             On 21.02.2016 12:32, SangHyuk Kim wrote:
>>>>             Hi, I transmit simple text file using two USRP N210
>>>>
>>>>             Tx)
>>>>             file source -> packet encoding -> mod(GMSK) -> usrp sink
>>>>
>>>>             Rx)
>>>>             usrp source -> demod(GMSK) -> packet decoding -> file sink
>>>>
>>>>
>>>>             To make corrupt packet, I tried to modify part of crc check
>>>>
>>>>             I guess if the crc of received packet doesn't match
>>>>             with original one, receiver would discard the packet.
>>>>
>>>>             However, I found receiver accepts every packet even if
>>>>             crc check returns 'false'.
>>>>             (I expected receiver accepts packet only pass crc check
>>>>             by 'true')
>>>>
>>>>              Why it always return false and how can I corrupt
>>>>             packet with other ways ?
>>>>
>>>>
>>>>             _______________________________________________
>>>>             Discuss-gnuradio mailing list
>>>>             [email protected] <mailto:[email protected]>
>>>>             https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>>
>>>
>>>             _______________________________________________
>>>             Discuss-gnuradio mailing list
>>>             [email protected] <mailto:[email protected]>
>>>             https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>>>
>>>
>>
>>
>
>

_______________________________________________
Discuss-gnuradio mailing list
[email protected]
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio

Reply via email to