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CPAM reader decode failed event message

Can anyone explain to me what exactly happens when the event 'reader decode failed' occurs?  The Log Code is GW.EV_READER_DECODE_FAILED.  There is not any additional information given in the event details.  I assume that the RFID reader was unable to successfully read the card and therefore was unable to lookup the credential.

We have this occur intermittently with a few door readers.  For the people who are experienced with RFID readers, is this normal behavior?  For instance, one of our door readers has the following Extended Status in the Hardware window.  370/10373 = 0.03566  That is almost a 4% failure rate on reading credentials.  TIA for any help.

Admin State: Admin Up

Interrupts: 92116

Zeros: 24035

Ones: 22023

CP interrupts: 0

Bits: 46058

Total frames: 10003

Timeouts: 0

Decodes: 10003

Decode failures: 370

Cisco Employee

Hi Harris

to your question 'reader decode failed' : it means the Primary data section has some error which could be (encoding,begin bit position,no of bits etc) when the badge is swiped.

Now since it is only happening intermittently, add some twist . To troubleshoot i would go and check

is it happening with some specific cards ?

is my credential setting are according to the cards used ?




You must check the D0 and D1 wires.  They are normally the green and white wires.  Thats normally the issue.


I realize we are necro-posting here, but I thought I would throw my 2 cents in.  I had a similar issue with some readers that were occasionally logging these errors at one customer site.  In that instance, they were using Card + PIN on readers with keypads (HID 5355KP).  I was going crazy reconnecting, replacing the readers, testing for interfence on the lines, hooking up the shield drains, etc. 

I finally camped at one of the 'problem' doors in the morning when the problem was most prevalent.  In my case, the problem turned out to be partially end user error as the users were double swiping their cards.  Basically, they would swipe and then with the card in the same hand, go to enter their PIN which caused a second card read.  This severely annoyed the reader and / or the door module, requiring the timeout to elapse before it can be tried again.  In my case, the error message was a bit misleading.  I duplicated this in the lab and opened a TAC case and the response was 'expected behavior' given the circumstances.

Anyway, might not be your issue, but might be somebody's.



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