Specifications

8-17
User Patterns and Disk Operation
Disk Operation
Unable to Write to Disk
A similar problem to running out of disk space is that of being unable to write to the disk
inserted in the drive. Possible reasons for this problem are:
1. Thereisnodiskinthedrivetowriteto.
2. The write-protect tab on the disk is set to prevent writing.
3. There is a hardware fault.
When a write operation fails within the editor, a simple error message is shown at the
bottom of the screen and the user remains in the editor, with the pattern intact.
Disk Organization
Although DOS supports a hierarchical directory structure, the instrument only looks for
pattern files in the topmost root directory.
The patterns are stored, one per file, in the root directory. A similar file is also present to
store the data in the buffer used during and . The pattern
files are named in some consistent manner, for example:
HPPATTO1.DAT - HPPATTO8.DAT.
On DOS there are no system-defined file types, but the files are tagged with one of the
conventional suffixes, DAT,toindicateadatafile.
The format of information held in a pattern or the buffer file is shown in Table 8-1. It
should be noted that all integers are held in unsigned representation. The file containing
the buffer data has a fixed label Buffer, and a pattern index of 0.
block save block load