[Argh! Following up my own post :-(] > I am looking for any information on a National Semiconductor RAM board that I > think goes in > a VAX 11/730. My 11/730 (which admittedly I have not run) has 2 DEC MS730 > boards and 2 of these > NatSemi boards, I found another one while unpacking stuff today.
[...] > The only identification I can find on it is in the etch : > > PWB 551109464-002 B > PWA 980109464 [...] > There seems to be one RAM too many!. The main RAM array is 4 rows each of 32 > 4164-like DRAMs. > Rest of the board is TTL drivers, etc. There are 2 LEDs, one green, one > yellow. And a momentary pushbutton > switch. I have no idea of the functions of those. That switch may well be latching (alternate action). I wasnt't pressing it hard enough. It seems to be wired directly to the yellow LED (amongst other things). I have found a mention of this board in an 11/750 FAQ (not surprising, I think the same 1M boards can be used in the 11/750 and 11/730). It appears that in normal operation both LEDs are on. Pressing the button turns off the yellow LED and completely disables the board. Quite why you'd want to do this I do not know... Oh, and it mentions a 'spare RAM chip in a socket on the board'. All RAM on my board is, indeed, socketed. If this is just an unused chip to substitute if one fails then I think I've seen it all... -tony
