From mboxrd@z Thu Jan 1 00:00:00 1970 From: chpap@ics.forth.gr (Christos Papachristou) Date: Wed, 26 Feb 2003 18:57:55 +0200 Subject: [pups] (no subject) References: Message-ID: <006901c2ddb8$3599d470$77b95b8b@ics.forth.gr> ----- Original Message ----- From: "Johnny Billquist" To: "Christos Papachristou" Cc: Sent: Wednesday, February 26, 2003 3:04 PM Subject: Re: [pups] (no subject) > On Wed, 26 Feb 2003, Christos Papachristou wrote: > > > A few questions from a newbie: > > I have installed 2.9BSD on a microPDP11/73 with an RD52, using the MSCP > > version of Jonathan Engdahl. After startup the kernel > > indicates 160kb of memory .I am not familiar with such an old unix to > > find out the details but I understand it as 256k minus the kernel. The memory > > is M8067-LF i.e. 512k Qbus. Does this mean that the system can't see the > > rest of it and that I have configure/recompile the kernel? > > The system seems anyway to run fine. > > Are you sure it's reporting bytes, and not words? I don't know ,it just says mem=158720 > > > I haven't seen an operational PDP with UNIX before this, > > so I can't judge its speed. When in single user mode it seems to > > me that it runs "fast". However upon entering multi user mode the speed > > drops dramaticaly. I have not yet compiled in the 8 port multiplexer > > (DHV11-A), so only the console is functional and thus no gettys are > > loaded. So ,why is there such a change in speed? Does the multiuser mode > > just rise the nice value of the console tasks? > > There shouldn't be a big difference in speed. Are you starting some heavy > demons? No. It wasn't a problem in speed, the default configuration for getty was wrong (it was configured for LA36 printer output). This is the first time I use a UNIX that was meant for dialups with 110-9600 modems or terminals so please excuse me. But I am learning... By the way the console runs at 38.4kbps , but the gettys are internaly configured at other speeds , the highest being 9.6kbps. Can't I use the full speed of the port? > > Some information on the system. It is a KDJ11-B (M8190 -no suffix) i.e. an > > 11/84. So, the label on the system says microPDP11/73 (in an BA23 enclosure) > > the cpu is an 11/84 (if the FPU socket is the DIP-40 slot then it is > > unused), and the 2.11BSD second stage boot (version from vtserver) I > > have tried indicates 11/83. The memory is after the CPU and is Qbus (M867-LF). > > If I have understood what I have read in the list, this must be a mixed > > system that could use PMI memory, but just uses Qbus?? What exactly is my > > system? > > There exists a specific 11/73 CPU card, but we'll ignore that for now. > The 11/73, 11/83 and 11/84 all use the same CPU card. > The differences are in other areas, and cannot always easily be detected > by software. > The difference between an 11/73 and 11/83 is if the system have Qbus > memory or PMI memory. The difference between an 11/83 and 11/84 is if the > system have the KT84 (or whatever the card is called, my memory fails me > at the moment) Unibus map, which is a Q-bus to Unibus converter along with > the Unibus map required. The CPU is always on a Qbus, but in the 11/84, > nothing but CPU and PMI memory is on this bus. > > > Moreover the MSCP controller (M8639 YP i.e. RQDX1) > > the serial port multiplexer(M3104 i.e. DHV11-A) and the memory are Qbus while > > the cpu board is indicated as Unibus in the field guide. Can these two bus type > > s be mixed? (If yes , i would be tempted to abuse the dead VAX11/780 in the > > basement. Can this be done?). > > No. > As stated above, the CPU card is actually always Qbus. In the 11/84 you > have a bus adapter to connect the Unibus. > > > Anyway, I thought that the best choice of > > a UNIX for it since it only has an RD52 woulbe 2.9 BSD with MSCP support. > > Was this a good guess? > > Yes, since you probably don't want to pay a lot of money to Mentec for one > of their OSes. 2.11 is much nicer, but you'll want more memory and disk > space for that. > > Johnny > > Johnny Billquist || "I'm on a bus > || on a psychedelic trip > email: bqt at update.uu.se || Reading murder books > pdp is alive! || tryin' to stay hip" - B. Idol >