Err, not according to the "Small Computer Handbook" (1967 Edition), which covers the LINC-8 in detail - at least, as I understand it? See, for instance, pg. 307 "A LINC HALT instruction will also stop the LINC and return control to the PDP-8." And see also the "Operational Summary", pp. 308-309, and Chapter 7, "LINC - PDP-8 Intercommunication". Reading the handbook, it _seems_ like, in theory at least, the two machines could run simultaneously (albeit contending for memory bandwidth), although the canonical programming approach was to have one pause while the other ran. Or perhaps that supposition is incorrect, and the two couldn't correctly deal with contention for memory (although the LINC used the standard PDP-8 'data break' mechanism for access to memory, which was used by DMA devices such as disks, so the -8 should have been able to deal with it; perhaps the LINC couldn't); or perhaps there was some vital piece of circuitry shared by both? I wonder if any LINC-8's still exist? The bone I have with that description (which may be technically correct) is that it implies that prior to the PDP-12, there were only the two separate machines (PDP-8 and LINC). But I know I'm a stickler for small details... :-) Noel