> From: Douglas Taylor > Is there a document that describes the bank 7 memory page and what > addresses are reserved for what?
Here's one I collated from a large number of DEC manuals: http://ana-3.lcs.mit.edu/~jnc/tech/pdp11/UNIBUS_Registers.txt (Ignore the name, it applies to QBUS machines too.) > bootstrap is reserved for 173000, how many words are allowed there for > this? Well, the space from 773000-773776 (UNIBUS and Q18 - add '17' to the front for Q22) is used for ROMs, and is the most common; 173000 is of course the location QBUS processors can be configured to jump to on power on. 765000-776 in also used for some (e.g. M9301's). > How do the more complicated bootstraps, e.g. microPDP11-53, accommodate > this limitation? Bank switching; e.g. the BDV11, KDF11-B have a 'page control register' at 777520 which says which block of ROM is mapped into the 773000 block. Interestingly, the DEC standard ROMs for the BDV11 and KDF11-B _don't_ copy all the contents down to real memory, and run from there - the code is divided into 'pages', only one of which is mapped in at a time, and it's executed from the ROM. Noel