-----Original Message----- From: cctalk-bounces at classiccmp.org [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Pete Turnbull Sent: maandag 26 september 2005 12:59 To: General Discussion: On-Topic and Off-Topic Posts Subject: Re: difference between LSI-11 CPU's M7264 and M7270 On Sep 26 2005, 8:40, Gooijen, Henk wrote: > I cleaned the dust out of a small 4 slot card cage with the power > supply at the right side. I was never good at naming the BA box types,

> here is the description. When you look at the front side, the 4 slots

> at the left side, and the PSU is at the right side and has at the front

> switches (DC on/off, enable/halt, and LTC on/off) and 2 LEDs (DC on and

Sounds like the innards of a BA11-M, especially given the boards you have. Check the number on the backplane, it should be a H9270, which is an 18-bit serpentine backplane. Usually you draw the boards positions as seen from the rear (from the handles). Is the M7270 to the left of the M8044 when seen from that direction? It should be. What you've drawn is correct for the view from the handles. M8045 and M8044 are the same board but the 8045 has extra RAM for parity and a few extra components fitted to enable it. 8044 is MSV11-D (non-parity) and 8045 is MSV11-E (parity). What you have is not at all unusual. Yes, but you may need to alter a few things, starting with the memory. If your M7264 has 4KW/8KB memory on it, you'll either need to change the start address of the MSV11-D, to be at 020000(8) (= 8192 decimal), or disable the memory on the M7264. These processors can only address 64KB of memory, so if your MSV11 has much memory on it, you might want to disable the 8KB on the processor. If you do, you'll need to disable some other things to do with refresh and BRPLY -- the M7264 produces a refresh signal which you don't want on the bus, and responds to refreshes and memory accesses on the bus. The MSV11-D/E are available with 4K or 16K DRAMs, and either half- or fully-populated, hence they can be any of 8KB, 16KB, 32KB, or 64KB, known as MSV11-DA, -DB, DC, DD. The second letter on the handle, however, is different -- it tells you where the chips came from, not the size. Dunno. As far as I know, it just plugs into one of the MICROM sockets, where the KEV11 (EIS/FIS upgrade would go), so it may work on any version of the 11/03. If it's specific to one, it may be that it works on a KD11-J (M7264-YA, without memory) but not a KD11-F (M7264, with 4KW memory) because they are different board layouts. Or, more likely, vice versa. Yes, that would be best. -- Pete Peter Turnbull Network Manager University of York