The present invention provides a PCMCIA-compliant generic laptop computer or personal digital assistant ("PDA") device with an add-on module that together with the device forms a portable point of sale transaction terminal. The add-on module is a self-contained unit that includes a magnetic stripe reader or a smartcard reader with a PCMCIA-compatible interface. Optionally, the module also includes any or all of a pinpad unit, a printer unit, a fingerprint unit, a signature capture unit, and a virtual pinpad unit. The module housing includes a protruding snout-like member that includes a PCMCIA connector. This snout-like member on the module housing slides into the PCMCIA slot of the computer, PDA, or similar device to make mechanical and electrical connections. Software storable and executed by the computer or PDA device includes driver definitions and routines to permit the device to read and process information read by the module from the credit or smartcard. The device can communicate, wirelessly, with IR, or via telephone lines, with a remote host system to further process a transaction for which the card is being used. Additional software can also provide encryption, signature capture, and associated other transaction processing and security promoting functions.

A check or other document verification method in which a data encryption algorithm is applied to personal identification number (PIN) and selected other information particular to each document such as check number or amount of check. The resulting derivation is printed on the face of the document at the time the document is originated, in human readable form and possibly in machine readable form. The recipient of the document is issued a proprietary card, preferably an integrated circuit or "smart card", which contains an identical algorithm to that used when the document was originated. When the document holder presents a check for cashing or otherwise presents a document for verification, the cardholder is first identified with the card by inserting the card in a terminal and manually entering a PIN as is a common practice. Then the person who was given the document for validation, such as a check cashier, enters the selected information from the face of the document, which is processed utilizing the previously entered PIN and the algorithm from the card to derive a number. The number thus derived may be compared to the derivation which was printed on the document, visually or automatically by incorporating the capability within the terminal for reading the derived number from the face of the document. The proposed method thus validates the cardholder as the legitimate holder of the card, the cardholder as the legitimate holder of the document, and the document as having been legitimately produced for the specific cardholder.

An integrated point of sale terminal for processing multiple payment types including payment by check includes a compact housing, a processor, and memory. The housing has a base shaped to sit on a merchant counter and has a document slot for receiving a check. The processor is disposed in the housing, and the memory is in communication with the processor. The payment terminal is located at the point of sale during use to allow a store merchant to accept multiple payment types. The payment terminal further includes a magnetic ink character recognition device for reading a string of magnetic ink characters on the check. The magnetic ink character recognition device is affixed to the housing at the document slot and is in communication with the processor. Further, the payment terminal includes an imaging device for capturing an image of the check. The imaging device is affixed to the housing at the document slot and is in communication with the processor. The processor is programed to process multiple payment types including processing a checking account transaction when the check is placed in a document slot.

An electronic travelers cheque transaction terminal for use in a financial institution such as a bank for purposes of assisting in the sale, refund or encashment of travelers cheques, and used in combination with a host computer with which the terminal is connected by telephone communication lines and which provides authorization of travelers' cheque transactions, comprising a character recognition element for reading data from the travelers cheques being sold, encashed or refunded, and a control element including a control processing unit and a control program stored in memory. The program is used for controlling the verification of the status of the data, the receipt of authorization of the transaction upon verification of the data, and the storage of the data into another memory upon authorization of the transaction. The control further includes means for generating a "Buffer Full" signal when the storage of the second memory is at capacity.

A point of sale (POS) receipt printer that includes a selective release mechanism that converts the printer into a check account verifying machine. The conversion mechanism magnetizes and selectively reads the account and bank information from existing magnetic characters on a check presented face-up to the receipt printer. The mechanism includes a magnet to magnetize the characters and a read head to read and analyze the signal waveform from each character. The check is pressed up against the read head and the magnetic characters are read only after the printing carriage of the receipt printer has moved to a dead zone within the printer housing.