A DEVICE TO ALLOW COMMUNICATION BETWEEN A COMPUTER AND AN EXTERNAL UNIT

Abstract: The invention concerns a device to allow communication betwen a computer comprising a flexible-disk drive (5) and an external unit (7), such as a smartcard, which unit (7) is temporarily connected to the computer. The device consists of a connection means (1) for connection of the external unit (7) to the computer, an internal communication means (2) for reception of magnetic signals from the read/write head (6) of the flexible-disk drive (5) and conversion of said signals into sequential digital signals, and a control means (3) for reception of the sequential digital signals, interpretation of said signals and conversion thereof into parallel digital signals that are transferable to the connection means (1) and further, to the external unit (7). Inversely, digital signals could be inputted from the external unit (7) and, after conversion in the control means (3) and the internal communication mean (2) be transferred to the read/write head (6) in the flexible-disk drive (5).

Description: A DEVICE TO ALLOW COMMUNICATION BETWEEN A COMPUTER AND AN EXTERNAL UNIT The subject invention concerns a device to allow communication between a computer comprising a flexible- disk drive and an external unit which is temporarily connected to the computer, such as an IC card (ICC = Integrated Circuit Card), in the following referred to as smartcard, and means to allow communication with another computer system, printers or other external equipment. Personal computer as a rule comprise one or several flexible-disk drives that are used practically exclusively for entering into the computer of software that usually is copied into a permanent disk storage. The signals generated by a disk are directly transferable to the station read/write head. To enable a computer to communicate with e.g. a smartcard, which often is essential in order for instance to identify the user of the computer or to perform various operations with the aid of the smartcard, special card reading means are required. A means of this kind is then connected to one of the external ports with which the computer usually is equipped. Normally, these ports are however occupied by a connected modem or a printer. To connect additional devices, supplementary equipment usually is required, such as e.g. a switching device. It is easily understood that as a consequence of the use of such supplementary equipment the risk of errors increases. The purpose of the invention is to provide a device which, when placed in the position of a disk in the computer, is able to provide for communication between an external unit, such as an smartcard, and the computer by way of the computer flexible-disk drive. This purpose is achieved by means of a device consisting of a connecting means, an internal communication means, and a control means which are characterized by the features appearing from the appendant claims. The invention will be described in closer detail in the following with reference to the accompanying drawings, wherein Fig. 1 illustrates the device schematically in a lateral view, and Fig. 2 illustrates the device in a plan view. The device consists of the three means, viz. the connection means 1, the internal communication means 2, and the control means 3, all of which are integrated into one single unit 4. This unit 4 is insertable into a computor at the place in the computer flexible-disk drive 5 (only suggested in the drawing) which is intended for reception of the computer disk. In accordance with prior-art technology information is stored in the form of magnetic signals sequentially on a disk, i.e. the information data bits are positioned in succession, one after the other. This storage technology is denominated MFM. When a disk is being read the magnetic signals are converted in the read/write head 6 of the flexible-disk drive into electrical signals in the form of voltage variations, to be further processed in a manner known per se into digital signals in a signal converter. Inversely, digital signals from the computer are converted in the read/write head 6 of the flexible-disk drive 5 into magnetic signals which are transferred to the disk and stored thereon. The internal communication means 2 of the device is designed in such a manner as to sense the magnetic signals generated by the read/write head 6 of the flexible-disk drive 5 and normally intended to magnetize the disk that is inserted into the flexible-disk drive 5. The signal language of the internal communication means 2 is so to speak the same as that of the flexible-disk drive 5, thus enabling signals to be transferred from the computor to the device via the flexible-disk drive 5. In the internal communication means 2 the magnetic signals are converted into digital signals in a sequential form and these signals are then transferred to the control means 3. The internal communication means 2 is furthermore designed to be able to receive digital signals from the control means 3 and to convert them into magnetic signals which may be read by the read/write head 6 of the flexible-disk drive 5. In this manner the digital signals may be transferred via the flexible-disk drive 5 from the device to the computer for processing. In the transfer of digital signals to an external unit 7, illustrated in the drawing as a smartcard, this unit 7 requires on the one hand that the signals are supplied on several parallel lines and on the other that the signal voltage levels are those indicated by the standard valid for the unit 7. The number of lines required may vary from just a few to some fifty or more, depending on the type of external unit 7 one wishes to connect to the device. The purpose of the device control means 3 is to effect conversion of the digital signals (in sequential form) that are transferred from the internal communication means 2. This conversion involves an interpretation of the signals and translation therof into signals that are right for the external unit 7 in question. In addition, the signals are to be distributed over a number of parallel lines in the transfer to the device connection means 1. This connection means 1 is used to transfer signals from the control means 3 to the external unit 7, for example to the smartcard illustrated in the drawing. The signals transferred to the external unit 7 may represent digital data to be processed by the external unit 7. The device 4 in accordance with the invention is, as mentioned previously, inserted at the place in the flexible-disk drive 5 where a disk is normally positioned, and thus constitutes an aid in the computer's communi- cation with an external unit 7. Instead of a smartcard this unit 7 could for instance be a PCMCIA card (Personal Computer Memory Card International Association), a means for communication with another computer system, a printer or other external equipment that may need to be connected to a computer. If for instance a smartcard is inserted into the connection means 1 user identification is easily established by transfer of information in the form of digital signals from several parallel lines via the connection means 1 to the control means 3, the latter interpreting the signals and converting them to serial digital signals that are transferred on a line to the internal communication means 2, whereupon the latter means converts the signals into signals that are intelligible to the computer flexible-disk drive 5. A protocol is stored in the device control means 3 to allow conversion of the signals emitted by the smartcard. A signal order transmitted from the computer flexible-disk drive 5 to the external unit 7 could be e.g. of the following nature, viz.: store information, supply sign or activate modem. The device is an integrated separate unit which is only temporarily inserted into the computer flexible-disk drive 5. This means that the flexible-disk drive 5 is always used in the conventional way when no external unit 7 need to be connected to the computer.

Claims: CLAIM A device to allow communication between a computer comprising a flexible-disk drive (5) and an external unit (7) which is temporarily connected to the computer, such as a smartcard, means for communication with another computer system, printers, or other external equipment, c h a r a c t e r i z e d in that the device consists of a connection means (1) for connection of the external unit (7) to the computer, an internal communication means (2) for reception of magnetic signals from the flexible-disk drive (5) and conversion of said signals to sequential digital signals, and a control means (3) for reception of the sequential digital signals, interpretation of said signals and conversion thereof into parallel digital signals that are transferable to the connection means (1) and further to the external unit (7), or vice versa, for reception of digital signals from the external unit (7) via the connection means (1), conversion of said signals and transfer thereof to the internal communication means (2) in a form intelligible to the latter to allow said means to convert the signal into magnetic signals and transfer thereof to the flexible-disk drive (5).

Inventors: ANDERSSON HANS OLOF, JOHANSSON ANDERS, ANDERSSON, HANS, OLOF, JOHANSSON, ANDERS
Applicants: ANDERSSON HANS OLOF, HANDELSBOLAGET STALCASTIN, JOHANSSON ANDERS, ANDERSSON, HANS, OLOF, JOHANSSON, ANDERS
Application year: 1995
Main classification: G06F1
IPC codes: G06F13, G06K7