Defining Disk Image Dump Standard

Let's start sort of from scratch here. So far we have the following (high level) criterion for a disk archive standard: 1. Host computer type (2 bytes allowing up to 65536 models to be specified) 2. Track format (host computer specific) 3. Sector format (single-density, double-density, etc) 4. Sector data format - this will specify what format the archived sector is in (raw data? logical bytes?) 5. Bytes per sector 6. Bits per byte What else? I will be the first to say that this is may not be very logically structured. What I am attempting to do is give a suggestion for a high level header that identifies what each chunk of data in the archive can represent. In this way, disks that are formatted with several different formats can be described. I think what this may evolve into is a Data Definition Language. The DDL will be encoded along with the disk data and will describe the format of the data on the disk as it is being read. This comes back to the fact that utilities will have to be written for each computer we decide to support (I assume it will be all of them) to both read and write native diskettes. I also assume the data will be passed between the archive host and the target machine via serial link? In case my mostly random thoughts above don't make sense, here is what I would have in mind for the Apple ][: The disk can be read in either standard, logical format (13 or 16 sectors per track, 256 bytes per sector) or "raw" format (raw disk bytes are read specially formatted tracks such as the 18-sector type I mentioned. As for reading the raw bytes, the Apple ][ had what were called "synchronization" bytes, which were 10 bits long, the two extra bits being used to synchronize the head with the start of the track. I could go into a technical discussion of this but would have to pull out some reference material to refresh my memory of how it all worked. Anyway, these bytes would have to be specially encoded in the archive. Sellam International Man of Intrigue and Danger ------------------------------------------------------------------------------- Looking for a six in a pile of nines... Coming soon: VCF 4.0! VCF East: Planning in Progress See http://www.vintage.org for details!