Disk Standard for Recording and Handling Detected Bad Sectors

This document, DEC STD 144, outlines a standard for identifying and handling bad sectors on disk cartridges, specifically the RK06 and RK07. It covers both hardware and software aspects of this process. The standard defines the format used at the manufacturing site to record the locations of surface errors on the disk. It also specifies responsibilities for manufacturing, engineering, and operating system software to ensure reliable handling of these manufacturing-determined bad sectors, aiming to prevent errors from occurring when attempting to read or write them. The document details two methods for identifying bad sectors: clearing a "good sector flag" in the header of the bad sector and listing them in a dedicated "bad sector file" on the highest numbered track. It also addresses how different operating systems, both small and large, should conform to this standard by either allocating bad sectors to inaccessible files or marking them as in use to prevent user access. The standard emphasizes that it does not require systems to remap bad blocks to make them appear contiguous to the user.