Which Dec Emulation is the MOST useful and Versatile?
computerdoc at sc.rr.com
Tue Oct 24 21:40:01 CDT 2017
I think I know so little of the PDP systems that I really didn't know how to
correctly phrase the question in PDP speak in my 1st email so let me try.
I was initially thinking of a strictly software only solution running on my
Windows 7 x64 laptop only since the only hardware based simulator I have is
the PiDP-8/I which is not up and running yet.
I'm primarily a Motorola Processor man so after sending that 1st email I
found a gentleman's web site who built a PDP-11 Console front panel using a
6802 on the core board at 1st then redesigned the core board to use the 6809
and an I/O board working together as the controller for the PDP-11 front
panel. The core board's serial port is connected to a PC running SimH
modified to communicate needed data to the front panel controller. The url
link to his web site is below.
Click on the "My Projects" link on the left to see a quick summary of all of
his homebrew projects of which this is only one. Now back to the core
Of course the 6809 can be replaced with the 6309 as well. Well, that really
sparked my interest as I am in the middle of designing a Motorola
Multi-Processor based single board computer board. It will have the ability
to support all of the following processors however ONLY 1 CPU can be
populated on the PCB at a time as ALL address, data and control busses are
tied together using one common flash/eprom, ram, 2 serial ports and 4 -
8-bit parallel ports with 2 special control bits on each port. The
processors that will be supported are the 6802, 6809, 6309 and the following
68HC11 sub-variants A1, A8, E2, F1 & K1.
So now my software only DEC Emulation idea is splitting into 2 thought
1st, a software simulator only way yields all currently supported PDPs which
still presents a problem for me and that is which PDP do I teach myself and
set up. So far, it seems that you guys are saying that the PDP-11/70 is a
good choice whether SimH or Erzata-11 is used.
A while back I found the PDP-8/e WinEight software simulator as one choice
as well. SIMH can run them all. Still though, which one?
2nd, a hardware emulator running a simulator written in 6809 assembly
language for the PDP-8/e running on a 6809 Core & I/O board system seems
like a good choice for me as I understand the 6809 microprocessor, the 6821
Peripheral Interface Adapter and the 6850 Asynchronous Communications
Interface Adapter chips used on the core board reasonably well.
There is a PDP-11 version of this hardware emulator available with only 1
more requirement and that is SIMH is running on a PC which communicates via
serial port the data needed to control the PDP-11 front panel.
3rd, and this is a big factor in the choice of DEC PDP computer to pick for
simulation or emulation and that is the small cash flow and itty bitty
storage space I have available to me.
So with what I have to work with, my current interests and skill level of
PCB design using the Motorola 8-bit processors as well as using Windows 7
x64 for software only simulations, which PDP should I chose?
The choice so far it seems is the PDP-11/70. Remember I still have no idea
beyond some searching on the internet what boards and peripherals a
PDP-11/70 consists of. For that matter, I don't know what boards and
peripherals are in the PDP-8/e or PDP-8/I either.
I hope this helps you all understand me and my desires a little better.
Please keep your ideas, suggestions and questions coming. You have my
complete attention! I'm sitting on the edge of my seat as it were. :) I'm
beginning to see that this is going to be a very long term project. Cool!
I need something to keep my mind sharp. Take care my friends.
computerdoc at sc.rr.com
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Kip Koon
Sent: Tuesday, October 24, 2017 1:44 AM
To: 'General Discussion: On-Topic and Off-Topic Posts'
Subject: Which Dec Emulation is the MOST useful and Versatile?
Hi DEC Enthusiast's,
If I were to have to decide on just one model DEC PDP system to run in a DEC
Emulator, which one would be the most useful, versatile and has the most
software available for it?
I have only ever used a real PDP-8/e system way back in high school so I'm
not up to par on any other model of DEC PDP system and I only know BASIC on
the PDP-8/e so not much there either.
I hear a lot about the PDP-11. I found out that there were 16 major PDP
models at one time so I'm not too sure which one to pick.
I built Oscar Vermeulen's PiDP-8/I which I'm waiting on 1 part for. Other
than that project which is in a holding pattern at the moment, I have no
other PDP anything running in any form.
Back in the day when Bill Gates and company 1st started out, I had always
wondered how they developed their very 1st software program - Altair Basic.
I was pleasantly surprised one day when I saw a B/W photo of a young Bill
Gates bending over the operator at what looked like a very small computer.
Maybe it was just a terminal. I don't remember. I understand they did
software development on a DEC PDP of some sort.
Finding this out regenerated my interest in the DEC PDP line of computers.
I have many projects in the works already so I decided to setup a software
emulation of just one of the DEC PDP models. I have heard a lot about the
PDP-11 which if the information I read is correct was 16-bits. My PiDP-8/I
is 12 bits. I understand the PDP 10 was 36-bits and the PDP-15 was 18-bit.
The PDP-11 is the model I hear the most about.
I also have some experience on some version of a VAX when I was in the Air
Force so I'm thinking of getting a VAX emulation going at some point too.
So if I'm going to do this, what suggestions, pointers, experiences,
etcetera do you guys have for me. I am very interested in the DEC PDP
equipment though next to no experience so I have no basis to make a
decision. This is a serious request so I would definitely like to hear what
you all have to say. If you have read this far, thank you. Take care my
computerdoc at sc.rr.com
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