Read/Write Wrap for Diskette Controller
Original Publication Date: 1985-May-01
Included in the Prior Art Database: 2005-Feb-18
Testing the attachment logic that interfaces to a diskette drive has always been a problem, in that it was hard to distinguish whether the error occurred in the attachment card or in the diskette drive. Issuing write and read data commands without actually using the diskette drive allows isolating the attachment logic from the diskette drive. Fig. 1 shows the hardware needed to perform the read and write operations. The following inputs are used for the wrap function. - Read Command is active when a read wrap command is to be performed. This line is controlled by the user. - Write Command is active when a write wrap command is to be performed. This line is controlled by the user. - Data Clock has the same frequency as the normal write control clock that controls the frequency of write data.