To minimize interference between digital control symbols and to permit data transmission on a data bus by giving additional time to detect data transmitted on the data bus to a REQ detection circuit by temporarily pausing for a preliminarily defined period.

This method transmits data in a two-way from a sender to a receiver via a data bus 15. In a certain example, a sender is defined as a host computer system 10, a receiver is defined as peripheral equipment for transmitting data from the host computer 10 to a disk drive 5 and data are transmitted from the drive 5 to the system 10 through the bus 15. A REQ detection circuit is given time when data transmitted on the bus 15 are detected by pausing for a preliminarily defined period, and interference between digital control symbols is minimized by that when data transmission is performed from the sender to the receiver.