6.3.17 Password Attempts Counters (PAC)

Each of the sixteen PAC fields contains an 8-bit attempts counter for the verify password process. Each PAC corresponds to a password. The attempts counter limits the number of consecutive incorrect presentations of the corresponding password to four, after which it locks the password from future use. The PAC will decrement ($FF, $EE, $CC, $88, $00) with each incorrect attempt to present the password. The PAC permanently locks the corresponding password once its value reaches $00. Prior to reaching $00, any correct presentation of the password resets the PAC value to $FF.