Tony Jones writes:
Hi.
I'm not expecting anyone will know the answer to this (I get the feeling few own a 9100 and fewer make much use of it) but I'll ask regardless, hope springs eternal.
Does anyone know of a use case where the 9100 system software requires that the disk change feature functions correctly? What's the "disk change feature" you might ask? There is a test for it in section 4-75 of the 9100FT service manual. Basically when the disk is changed an interrupt is raised through DTIO#2. The test in the manual is basically that subsequent iterations of the same operation should not access the disk unless the disk has been changed between iterations.
However I'm not aware of any part of the software that relies on this feature working. When loading the system sw from multiple floppies, there is a manual keystroke required to flag a disk change.
Other systems I’ve worked on will cache the disk directory when you read a floppy, then use the disk change line to know if the cache should be flushed. The 9100 might be similar, maybe try tying the line low and reading two userdisks in succession. -- Ian _______________________________________________ Techtoolslist mailing list Techtoolslist@flippers.com https://pairlist7.pair.net/mailman/listinfo/techtoolslist FTP site is: ftp://ttl.arcadetech.org/TTL/Test_Equipment Archive site: http://seven.pairlist.net/pipermail/techtoolslist/