Example Of "Base 95; Example Of "Exclusive Or" Algorithm - Comtech EF Data XTRT-400C Operation And Installation Manual

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"Base 95"
"Exclusive OR"

Example of "Base 95"

Message ("ID/Version" Query): {A0}
1 Take Sum of Message Bytes
2. Subtract 32
3. Modulus 95
4. Add 32

Example of "Exclusive OR" Algorithm

Message ("ID/Version" Query): STX A 0 ETX (ASCII)
Progressively XORs the bytes to establish the check byte
Check byte = STX ^ A ^ 0 ^ ETX = ASCII character (may be non-
printable)
thus:
MNC-0500-038
EAR EXPORT CONTROLLED: The information contained in this Manual refers or relates to a product that is subject
to the U.S. Export Administration Regulations (EAR). Transfer of data herein by any means to a Foreign Person,
whether in the U.S. or abroad, may require an export license from the U.S. Department of Commerce.
Amplifier Communication and Protocol, XTRT, Touchscreen TWTA
Table 3, Check Byte Calculation
1. Take [Sum (all message bytes)] – 32 = C
2. Then take [Modulus C ("Base 95")] + 32 = Result (Printable ASCII
character in range of 32 to 126)
XOR (all message bytes) = Result (non-printable byte)
'{' + 'A' + '0' + '}'
123 + 65 + 48 + 125 = 361
361 – 32 = 329
329% 95 = 44
44 + 32 = 76 (ASCII 'L')
9 of 28
Revision 2

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