BWS-136 User Manual_amend.doc
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Echo Syntax
After BWS-136 console port received correct command string, it
will response Echo String and the Echo Syntax is as follow:
[Delimiter][Function][Status]
Delimiter (One byte): A percentage sign “%”
Function (Two bytes): function string
Status: “OK” or “FAIL”
For example: Set the IP Address by sending command
$SLI192.168.16.100
(CR)(LF)
Echo string
%SLIOK
(CR)(LF)
means the new IP address is successfully transferred to the module
and the new setting will be effective after reboot the module.
To get IP address setting, you can send a command as follow
$GLI
then the Echo string will be
%GLI192.168.16.100
Always remember to reboot the module by send command
$SYCR
to use the new configuration
BWS-136 User Manual_amend.doc
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Appendix A
Tiny Encryption Algorithm
1.
Example of TEA.C
/************************************************
The Tiny Encryption Algorithm (TEA) by David Wheeler and Roger Needham of the
Cambridge Computer Laboratory. Placed in the Public Domain by
David Wheeler and Roger Needham.
**** ANSI C VERSION (New Variant) ****
Notes:TEA is a Feistel cipher with XOR and addition as the non-linear mixing
functions.
Takes 64 bits of data in v[0] and v[1]. Returns 64 bits of data in w[0] and w[1].
Takes 128 bits of key in k[0] - k[3].
TEA can be operated in any of the modes of DES. Cipher Block Chaining is, for
example, simple to implement. n is the number of iterations. 32 is ample,
16 is sufficient, as few as eight may be OK. The algorithm achieves good
dispersion after six iterations. The iteration count can be made variable if
required.
Note this is optimised for 32-bit CPUs with fast shift capabilities. It can very
easily be ported to assembly language on most CPUs. delta is chosen to be the
real part of (the golden ratio Sqrt(5/4) - 1/2 ~ 0.618034 multiplied by 2^32).
This version has been amended to foil two weaknesses identified by David A.
Wagner ([email protected]): 1) effective key length of old-variant TEA was
126 not 128 bits 2) a related key attack was possible
