Apparatus and method for transferring fault data from a recording device to a data processor

摘要

Error information is passed across a limited interface (10) from a disk drive to its using system by making use of the read data line during a fault mode operation. Fault mode operation is detected by a pulse width detector (46) in an adapter between the using system and the disk drive. The pulse width detector detects the presence of a fault signal on the read data line and inhibits the passage of the spindle motor on (MTR ON) signal from the using system to the disk drive. The step signal (STEP) normally used to index the recording head is passed to the disk drive during fault mode operation. A microcomputer (30) at the disk drive detects the absence of the MTR ON signal and the presence of the step signal and outputs a fault data bit. Thereafter, the fault data word is gated onto the read data line at the rate of one bit per step so long as the MTR ON signal is absent.