Methods for secure transactions between gaming machines and portable devices are described. A logic device, separate from a master gaming controller on the gaming machine and placed in the gaming machine, may be operable to authenticate a portable device, such as a smart card, and authorize transactions involving transfers of indicia of credit between the portable device and the gaming machine. The logic device may be operable to send authentication information relating to the portable device to a remote host where a value amount of transactions involving the portable device authorized by the logic device may be higher when the logic device and the remote host authenticate the portable device as opposed to when the portable device is only authenticated by the logic device.