Adapter aid for the trouble-free connection of computer peripherals to a device interface controlled by computer systems

Claim 1

An arrangement for the trouble-free connection of computer peripherals to a multi-pole device interface controlled by at least one computer system to which computer peripherals can be connected in parallel fashion, and which is composed of bidirectionally effective data interface contacts and bidirectionally and unidirectionally effective control interface contacts, said data and control contacts being controlled by said computer system and/or the computer peripherals, and the said data and control interface contacts being provided at the said computer system and at the said computer peripherals, respectively, with defined terminating impedances, and asymmetrical digital data and control signals to be transmitted via a device interface or via interface cables being limited to a prescribed maximum length and emitted within prescribed voltage level values or, respectively, received within prescribed voltage level values in evaluatable fashion, including, in combination; an adapter aid (ADE) incorporated between the said computer system (RE) and the said computer peripherals (PE), said adapter aid (ADE) including a device interface (PS) connected to said computer system (RE) and including an additional device interface (PSZ) connected to a said computer peripheral (PE), said device interface (PS) and said additional device interface (PSZ) having data and control interface contacts provided with prescribed terminating resistances (R), the said bidirectionally effective data and control interface contacts (SCL), BSY, D1-D8, DP) of the device interfaces (PS, PSZ) being connected via bidirectionally controllable, selectively switchable first switching means (BST, LTE, DPST), the unidirectionally effective control interface contacts (BSY, ATN, ACK, RST, MSG, I/O, C/D, REQ) of the two device interface (PS, PSZ) being connected via unidirectionally controllable, selectively switchable second switching means (BT), and the first and second switching means (BST, LTE, DPST, BT) being adapted to be switched effectively via a control interface contact (CTAN) arranged in the said additional device interface (PSZ), with the assistance of third switching means (KS) and logic elements V, N by a computer peripheral (PE) actively connected at the additional device interface (PSZ), logic means for detecting whether information is currently being transmitted via the device interface (PS) by one of the parallely arranged computer peripherals (PE) or said computer system (RE), said third switching means being connected to said logic means and responsive thereto.