3 ms·

this is an excellent project that's great fun to watch the progress of. keep up the great work. i have no experience with altos but i have been wondering -- on

this is an excellent project that's great fun to watch the progress of. keep up the great work. i have no experience with altos but i have been wondering -- on day one of the restore, it was noted the alto in question had some modifications from stock issue[1], could the booting issues be related to the microcode or wiring changes necessary to support those modifications? is it trying to boot off of the now missing trident drive? [1] from http://www.righto.com/2016/06/restoring-y-combinators-xerox-alto-day.html http://www.righto.com/2016/06/restoring-y-combinators-xerox-... "I suspect that the Y Combinator Alto originally had both a Trident drive and a Diablo drive (as well as four Orbit boards to drive a laser printer)"

kens 10y ago
That's an interesting question. From reading the documentation [1], the Trident disk should co-exist with the standard disk. It uses different microcode tasks (3 and 15), requiring additional microcode. No wiring change is mentioned (or discussion of booting off the Trident disk). It seems like the Trident drive shouldn't be causing us any problems, but it's possible there's a wiring change or different PROMs. I guess we'll find out... [1] http://bitsavers.org/pdf/xerox/alto/ifs_trident/TriconDoc.pdf http://bitsavers.org/pdf/xerox/alto/ifs_trident/TriconDoc.pd...