UHAC010@VAXA.RHBNC.AC.UK (05/12/88)
I don't know anything about 2000 memory expansion units but I do know that the microVAX 2000 and the VAXstation 2000 have a lot more in common than DEC would like you to know. To keep production costs down there is a single motherboard with links that allow customisation. The Ethernet interface is on a separate piggy-back board (as is the memory) but I think I'm right in saying that the graphics hardware is on the motherboard, at least for the monochrome machine. The ROMs for both machines certainly are. So all you people out there with straight 2000s can have a VAXstation for the price of a VR260 monitor. mouse and a keyboard (OK so its not that much of a bargain...) The mouse and keyboard are driven by two of the 2000's four serial ports. There are different connectors sticking out of the box but the electronics is the same. Therefore it seems inconceivable that a memory expansion for the straight 2000 would not work in a VAXstation because they're the same thing. Another point of interest is that the beasts have far more expansion capability than has been let on. There are several edge connectors on the board and the GPX style graphics subsystems for the colour machines just plug in as does an eight line mux (I believe) and of course the Ethernet board. What we need is some enterprising manufacturer to run one of these connectors out of the box and wrap some asynchronous Qbus logic round it and we'd have One Cheap Vax (expandable model). If someone wants to tell me the 2000 internal bus structure I'll design the Q-bus expansion unit for them... Finally, I run 21 VS 2000s along with five other assorted GPX's and servers. I find the VR260 (monochrome) monitors blow their fuse with alarming ease. We had a power brown-out the other day and lost eight out of ten! I know that there has been an internal DEC FCO to fix this but my local office don't know anything about this. (Maybe it's just to fit a six inch slow blow nail where the 20mm 500ma fuse is now.) Anyone got any experiences with this problem? ------------------------------------------------------------------------------ Adrian Johnstone, Mail: Royal Holloway & Bedford New College, Egham, Surrey, TW20 0EX, England Phone: 0784 39025 Fax: 0784 37520 Telex: 935504 RHC Email: Janet: A.JOHNSTONE@uk.ac.rhbnc.vaxa Arpa: A.JOHNSTONE%vaxa.rhbnc.ac.uk@cs.ucl.ac.uk Bitnet/NetNorth/Earn: A.JOHNSTONE@vaxa.rhbnc.ac.uk ------------------------------------------------------------------------------