From mboxrd@z Thu Jan 1 00:00:00 1970 From: cdl@mpl.ucsd.edu (Carl Lowenstein) Date: Wed, 12 Nov 2003 19:42:05 -0800 (PST) Subject: [pups] Re: A project--buiilding a device to plug into a PDP-11's bus Message-ID: <200311130342.hAD3g5Z17144@opihi.ucsd.edu> > Date: Thu, 13 Nov 2003 12:30:34 +1100 (EST) > From: John Holden > To: pups at minnie.tuhs.org > Subject: [pups] > Re: A project--buiilding a device to plug into a PDP-11's bus > > Gregg C Levine wrote :- > > > I also recall that the processor in question at one point in its > > lifespan, actually used the AM2901 family of bit-slice processors. > > DEC didn't use 2901's in central processors, but the FPU's for 11/34 and > 11/44 used 16 of them to make the 64 bit data path for the FPU. They were > also used in some peripherals like the KMC-11. At one time there was a set of application notes that described how to build a PDP11 clone out of AM2901 bit slices. I think that the performance would have been approximately that of an 11/40, while the time and effort and parts cost would have been prohibitive for a one-off production. It is barely possible that I have a set of those notes somewhere, although it would take a very lucky random search to find them. carl -- carl lowenstein marine physical lab u.c. san diego clowenst at ucsd.edu