36XX disk drive compatibility & cannibalism

[barmar@Think.COM (Barry Margolin)]

    Date: Tue, 18 Jun 1991 21:39 EDT
    From: RWK@fuji.ila.com (Robert W. Kerns)

	Date: Tue, 18 Jun 1991 13:23-0400
	From: barmar@think.com (Barry Margolin)

	Yes, these are all compatible.  The only incompatible pieces between
	3600's and other L-machines are the I/O board, I/O paddle, and the
	console.

    Actually, Barry, the I/O paddle determines what kind of
    disk drive a machine can use.  Eagles use the SMD interface.
    Both the 3600 and the 3670 use the SMD interface, but not
    all of the other models do, and there were various options at
    various times, so they're not ALL compatible.

True.  But the 3670's SMD I/O paddle can be used in a 3640; you just
have to replace three chips on the I/O board (it's too bad they didn't
put the alternate chips in dummy slots, the way they did on the Datapath
for the upgrade to an IFU).  The I/O boards are often labeled "3670 I/O"
and "3640 I/O"; the boards are the same, the only difference is which
set of disk interface chips is initially installed.

The 3600 I/O paddle can't be used in the 3670, and vice versa, because
the I/O board/paddle also contains the video interface, and the 3600
uses the old Lemo console.

                                                barmar