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

Back to Subject List

Old thread has been locked -- no new posts accepted in this thread
???
08/17/10 21:21
Read: times


 
Msg Score: +1
 +1 Good Answer/Helpful		 #178060 - + Error Checking?
Responding to: ???'s previous message
I agree a lot with Erik said; the environment + communication medium (electrical/transceivers) is quite relevant to the problem.

Also, I am assuming you are not using any method of error checking as you did not state that in your post.

If you implement some type of CRC and error checking method in your communication routine, you can ensure a message is valid, not just that a message was received.

Additionally, you could add a special byte command (or test routine, to isolate the problem(s) ) to require the slave to respond with its received bytes in case a message is detected as being invalid.

That way you'd know what was received.

It would be smart to assume that a percentage of messages would be invalid so that your system can respond as necessary to cope with erroneous messages (resend, etc.) without requiring a reset.

My $.02

List of 46 messages in thread
TopicAuthorDate
Multiprocessor Communication 8052            01/01/70 00:00      
   missing info            01/01/70 00:00      
      Hardware and slaves placement            01/01/70 00:00      
         How to TriState???            01/01/70 00:00      
            Using Tristate IC in Slave Card            01/01/70 00:00      
               at the receive ...            01/01/70 00:00      
               RE: I think that this IC handles the Tristate situation            01/01/70 00:00      
               then you need to read            01/01/70 00:00      
                  At the Master end            01/01/70 00:00      
                     again, you need a schmitt            01/01/70 00:00      
                        Hysterese            01/01/70 00:00      
                        Re: Thanks...Info about hardware we are using            01/01/70 00:00      
                           how do you know?            01/01/70 00:00      
                              Lowering baud rate            01/01/70 00:00      
                           Really            01/01/70 00:00      
                              Modified the code in Master and Slave            01/01/70 00:00      
                                 Haven't seen full code - slave protocol state fully cleared?            01/01/70 00:00      
                                    Slave protocol code            01/01/70 00:00      
                                       Slave send code fails to synchronize            01/01/70 00:00      
                                          breaking infinite waits in slave acknowledge wait            01/01/70 00:00      
                                       Stop fooling yourself            01/01/70 00:00      
                                          why didn't you before posting updated code            01/01/70 00:00      
                                          How to reset?            01/01/70 00:00      
                                             Hard reset by doing a hard reset.            01/01/70 00:00      
                                          Errors gone            01/01/70 00:00      
                                             But slave still doesn't synchronize with a resend request            01/01/70 00:00      
                                                that is not the way to do it            01/01/70 00:00      
                                                   too late for an edit            01/01/70 00:00      
      Reduced Baud Rate            01/01/70 00:00      
         not surprised            01/01/70 00:00      
            Never reboot for a transfer error            01/01/70 00:00      
               never be an afterthought            01/01/70 00:00      
                  Transfer validation before implementing command processing            01/01/70 00:00      
                     a trick            01/01/70 00:00      
                        address coding example required            01/01/70 00:00      
                           example            01/01/70 00:00      
                        Added "No message" byte            01/01/70 00:00      
                  never be an afterthought: Amen            01/01/70 00:00      
               Slave Recovery in Error            01/01/70 00:00      
                  Find out Why            01/01/70 00:00      
                     absolutely            01/01/70 00:00      
                        worse in the real world            01/01/70 00:00      
                  in addition: rise baudrate            01/01/70 00:00      
               Slaves follow Synchronization            01/01/70 00:00      
   + Error Checking?            01/01/70 00:00      
      It would be smart to assume that a percentage of messages...            01/01/70 00:00      

Back to Subject List