Controller using time-domain filter connected to a signal line to control a time at which signal line is sampled for receipt of information transfer signal

Abstract

The present invention is directed to providing a method and apparatus for improving the reliability of signal detection in signal lines used to receive information transfer signals such as the request and acknowledge signals of a small computer system interface, without degrading information transfer signals which are output from the small computer system interface and without inhibiting the use of both asynchronous and synchronous modes of information transfer. In accordance with exemplary embodiments, rather than using a filter to damp an incoming signal, a time-domain filter is used to determine when the incoming signal is expected to be valid. The time delay can, if desired, be programmed by the user so that the delay can be easily varied to account for specific signal conduits and peripheral devices. In accordance with exemplary embodiments, the information transfer signals can be received via the time-domain filter during an initial asynchronous mode of information transfer. A time delay of the time-domain filter can then be gradually reduced; if it is determined that reliability of signal detection remains relatively high, then information transfer can be switched to a synchronous mode, such that the filtered input signal line is disabled, and the information transfer signals can be both sent and received via the unfiltered output signal line.

Dependencies are inferred from the claim text.