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Trailing-Edge - PDP-10 Archives - cust_sup_cusp_bb-x130c-sb - 10,7/unscom/x680/x680.opr
There are 8 other files named x680.opr in the archive. Click here to see a list.
THE ASSEMBLY PROCEEDURE IS NON-TRIVIAL --
SEE 'X680 ASSEMBLY AND CONFIGURATION' IN SOFTWARE NOTEBOOK 5.