Email: Password: Remember Me | Create Account (Free)

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
08/10/11 09:25
Read: times


 
#183283 - RE: increase the error detection capability
Responding to: ???'s previous message
Oliver Sedlacek said:
I've each command as a single byte, and I've chosen from only the ASCII printable bytes. This means that all commands are atomic, and I can exercise my target from a terminal program without having to write a test app

Good thinking!

increase the error detection capability by chosing different command bytes

Not sure what you mean by that?

Do you mean having something like a "hamming distance" between your codes?

If so you might want to consider both the hamming distance between the code values - to protect against signal corruption - and the physical distance between the key on the keyboard - to protect against finger errors!

Alternatively, why not add a CRC or Checksum?
You could still represent the check code value using ASCII-only text (eg, as NMEA does);
You could arrange some "special case" value to indicate "do not check" - to make it easier when typing manually...

List of 13 messages in thread
TopicAuthorDate
Error detecting codes over RS232            01/01/70 00:00      
   RE: increase the error detection capability            01/01/70 00:00      
      How complex?            01/01/70 00:00      
      Hamming distance            01/01/70 00:00      
         Hamming distance really not a good choice            01/01/70 00:00      
            KISS            01/01/70 00:00      
               Transfer size?            01/01/70 00:00      
                  Transfer Size ---            01/01/70 00:00      
                     Parameter free            01/01/70 00:00      
                        Transfer Size ---            01/01/70 00:00      
   double command and CR            01/01/70 00:00      
      a bit more involved and better            01/01/70 00:00      
      Double Characters...            01/01/70 00:00      

Back to Subject List