User's Manual

HF Mifare Easy Module V1.0
ACG Identification Technologies GmbH 32
7.4.2 Error Codes
Following figure shows an overview of all error messages of the reader device.
Error Code Description
‘?’ Unknown command
'E' Invalid key format
‘F’ General failure
‘I’
Invalid value format, specified block does not match the value
format
‘N’ No tag in the field
'O' Operation mode failure
'U' Read after write failure
'X' Authentication failed
Figure 7-9: Error codes