On 01/08/2017 09:09 PM, Chuck Guzis wrote: > On 01/08/2017 04:42 PM, william degnan wrote: >> Inverse 8085? > I don't think so. If it helps, here's the first few lines of the > "directory": > > 000: 00 a1 7a c1 c0 00 00 > 0007: 00 00 00 00 00 00 00 80 1a 02 38 00 > 0013: a1 7a c1 c0 00 00 00 00 1b ff 00 00 > 001f: 5c 25 15 1b 4c 40 00 00 ff ff 37 05 > 002b: 94 2f 38 40 00 00 00 00 ff 8f 31 01 > 0037: c4 a3 75 6a ab 52 00 00 ff 85 25 05 > 0043: 94 2f 38 40 00 00 00 00 ff 02 0f 02 > 004f: c4 a3 75 6a ab 52 00 00 ff b6 09 04 > 005b: 94 2f 38 40 00 00 00 00 ff 03 02 03 > 0067: c4 a3 75 6a ab 52 00 00 ff 01 12 01 > 0073: d0 7f 9f 12 1f bd 53 28 ff ff 7f 02 > 007f: c4 a3 75 6a ab 52 00 00 ff 01 2b 00 > 008b: c4 a3 75 6a ab 52 00 00 ff 83 28 04 > 0097: c4 a3 75 6a ab 52 00 00 ff 01 38 00 > 00a3: 94 2f 3e 80 00 00 00 00 ff 01 1d 00 > 00af: 94 2f 4b 00 00 00 00 00 ff 03 35 05 > 00bb: 94 2f 4b 00 00 00 00 00 ff ff 3e 06 > ... > > There are no other tables on disk. The disk itself is hard-sectored, > with a sector length of 150 bytes and 16 sectors per track. They're > interleaved 3:1 and grouped into blocks of 1200 bytes. The directory > would correspond to block 0 and there are 72 entries in it, less the header. > > I can get the raw text, but how it's linked together and what file names > might is still a mystery. > > --Chuck > > I haven't ground on what it may be but there are four likely directory/catalog cases.
Bag and tag, the file name starting block (or group of blocks) and number of blocks. usually byte pairs or longer ((16, 24, or 32bits) to get enough addressing and large enough byte counts. CP/M like with entries for file name then a short list of allocation blocks, additional entries if the file is larger and needs for allocation blocks. FYI CPM it can be byte pairs or single byte allocation list. unix like with a simple filename and pointer to Inode there the metadata and block list is. Last case is a reserved set of blocks that are allocated as a linked list and the directory block has the filename and point to the start of the list. Like unix that can easily support subdirectories. None of those are processor specific but the cpu used often determines things like if there is bit packing. As to radix, anything is possible also simeple things like high bit of a 8bit byte suggests a control code or extended characters (or several things). Allison