TIHOR.CMCL1@NYU.ARPA (03/30/83)
From: Stephen Tihor <TIHOR.CMCL1@NYU.ARPA> The figures displayed at DECUS about the UDA50a controller disks indicated that one UDA50 controller uses ~52% of a Unibus [someone will no doubt no cite the exact figure] and has an explicit "Thou Shalt Not Steal All The Unibus Cycles" built in to insure that figure. Thus if you decide to get more than one CONTROLLER (up to 4 disks each) the recomendation was to get a second Unibus. The UDA50a also should not be put in the same Unibus with "high performance DMA devices" without testing the loads involved. Note that terminals and DMCs are not considered "high permformance DMA devices". If we get one it will go into the main Unibus cage and if we get a second it will go into the second Unibus as would a third (although I doubt we need 6+ disks.) -------