Providing Controller Power Good Signal to Disk File(s)
Original Publication Date: 1981-Oct-01
Included in the Prior Art Database: 2005-Feb-12
In some data processing system environments including magnetic disk files, the file control is implemented with the power to the files being independent of power to the interface controller. This means the interface controller can be either powered off or have power coming on, or have power going off while power remains on at the file. During power on and off conditions, glitching of the interface lines between the controller and the file may occur as power passes through the threshold regions of the interface drivers. Glitches on the "write' and drive select' interface lines can cause loss of data. The "write' and "drive select' lines are used to control the writing of data to the file.