Who wants a BeagleBone Black and BaconCape?

I would simulate an old computer and build a front panel with switches and blinkenlights and bells and whistles ... Sorry but I am a pdp8 fan. I hope that doesn't disqualify me!

Mike Roach wrote:

 

Sorry but I am a pdp8 fan. I hope that doesn't disqualify me!

Given the number of old timers here, it probably qualifies you for an E14 OAP Community discount.

I so regret having thrown away my old PDP-11 keyswitches on which entering the bootstrap loader manually each morning became totally automatic.  I did at least hold onto various PDP-11 racks, which continue to provide sterling service in the computer room and are quite likely to outlast humanity.

Michael Conners wrote:

 

I learned assembly on a pdp-11/23 in cheltenham. I won't say where, those in the know will know. I say assembly as I really learned machine code. We had to write our assembly out on a notepad, translate it to octal machine code, fingerbone it into the terminal, boot up xxdp+, then save the memory locations to a file.

 

It was great fun. By the end of the 3 week course I completely skipped the assembly step and was just writing octal digits.

 

I have to hand it to the instructor though, he'd look over my shoulder and he'd say, that 7 right there, don't you mean 5,and that 3 should be a 4, i'd look and sure enough he'd be right. That guy knew his stuff.

 

I used to have the flip switch boot sequence for the pdp-11/70 memorized. But that was a long time ago.

 

Mike

Ah yes, PDP-11 machine language is really easy to read and write in octal.  I spent so much time with PDP-11s in my undergrad days that I had trouble counting by twos in decimal... somehow it always came out 0, 2, 4, 6, 10, 12, 14, 16, 20, ...

I first used a PDP-11 in a computer organization course with a large assembly language programming project.  The first assignment -- to get you used to the PDP-11 -- was to write a small program to accept a keystroke and echo it back 10 times.  When I took the course, you had to hand-assemble it and key it in through the front panel.  This turned out to be a lot easier than learning to use the card reader, assembler, and linker.    Later versions of the course required students to use the tools for the first assignment so they'd be prepared for the larger assignments.

It was really great to have that experience. I wouldn't trade it for the world. Those of us that came up in that time got an experience I think alot of students are missing these days. They are so far removed from the CPU and allow the OS to dictate so much to them. I'm glad computer systems have evolved to where they are today, but knowing the nuts and bolts of something is a great treat.

MIke

Michael Conners wrote:

 

knowing the nuts and bolts of something is a great treat.

It is a treat, but it's more than just a treat.  I think it is absolutely essential for all engineers to understand completely the fundamentals of their profession, and without that knowledge they are just craftsmen practicing by rote instead of understanding what they do and why they do it at a deep level.

Ones and zeros are the bedrock of the digital computing professions (both hardware and software), and not being immersed in them during formative years creates an engineer that is about as useful as a civil engineer who skipped the course on materials.  They may still be able to pick parts out of a catalogue, but something very important is missing.

Yeah, you're right. What I meant was it is a treat for me and coming from the hardware side of things before getting into software I really cherish having that experience. I remember the thrill of hooking the o-scope or logic analyzer up to something that was once a bunch of components and making it behave as I commanded it. That has always meant more to me than any text based output or gui ever could.

I have seen some really excellent software craftsman that have never had the experience I have had though, and sometimes that is all you need. I'm not saying that it is always optimal, but sometimes that is all you need. I would recommend to any potential or current software engineers to get their hands dirty and take some hardware classes. Get some experience doing system administration as well. Get into hobby electronics, it's affordable now and there are plenty of options. It will make you a better craftsman and programmer.

Mike

Michael Conners wrote:

 

It was really great to have that experience. I wouldn't trade it for the world. Those of us that came up in that time got an experience I think alot of students are missing these days. They are so far removed from the CPU and allow the OS to dictate so much to them. I'm glad computer systems have evolved to where they are today, but knowing the nuts and bolts of something is a great treat.

I'm glad computer hardware has evolved to where it is now.  Now software, on the other hand...

John Beetem wrote:

 

I'm glad computer hardware has evolved to where it is now.  Now software, on the other hand...

... has devolved into less linguistic power than we had before (LISP was half a century ago, and most languages still haven't caught up), less security than we had before (running downloaded executables used to be only for the clueless, and now we have Javascript), and less availability than we had before (availability is a function of distance and points of failure, and now we have the "cloud" which multiplies them both N-fold).

Software today is not developed by engineers, even when they call themselves "software engineers".  It's developed by followers of "cool", and their god is a Bug and their altar a collapsing bridge.  These are truly sad days.

I used to lecture in Software Engineering.  I would be embarassed to do so now.  The so-called Software Crisis has never been deeper.

Morgaine.

Morgaine Dinova wrote:

 

John Beetem wrote:

 

I'm glad computer hardware has evolved to where it is now.  Now software, on the other hand...

...

 

The so-called Software Crisis has never been deeper.

Great comments, Morgaine.

Fortunately, there are still some processors and boards that do let you build your own software from the bare metal on up.  So for those who recognize the problem there is a path to do something about it.  They can expect lots of abuse, though.  Still, we can be encouraged by Margaret Mead's words:

Never doubt that a small group of committed people can change the world. Indeed, it is the only thing that ever has.

This thread has been an unexpected treat for me!  I love hearing about how it used to be back in the day before all the levels of abstraction got in the way (not that I don't like being able to browse the web wirelessly on my phone).  Maybe one day I'll convince the computer history museum to let into their storage to see the PDP-7 (my domain and handle on freenode and twitter).  At least they do have nice displays of PDP-8 and PDP-11 and a working PDP-1!

PDP-1 demo: https://plus.google.com/photos/117542001281850354871/albums/5876039181137247889

I really can't stay away from the place!

2010: https://plus.google.com/photos/117542001281850354871/albums/5476982068694660017

2012: https://plus.google.com/photos/117542001281850354871/albums/5745030180245599681

2013: https://plus.google.com/photos/117542001281850354871/albums/5876043512327434513

Luxury, when I was a lad I used to dream of having a teletype with tape punch and reader.....   oops sorry slipped into Monty Python mode.

My college experience was Fortran IV on a PDP8e but then I went on to work with many microprocessors in embedded systems using assembler and later C, it was the happiest time of my working career. Later on in life I ended up in senior management and bored. Now retired I have been tinkering with various devices dev boards, FPGAs, etc and loving every minute, maybe one day I will do something useful with them

Drew Fustini wrote:

 

At least they do have nice displays of PDP-8 and PDP-11 and a working PDP-1!

Oooh, that's a lovely little high-speed fan-fold paper tape reader!

In the class I mentioned above, you had to sign up for maybe an hour a day on a shared PDP-11, so you had to enter your programs off-line.  Most students used punched cards, but the punched card reader was quirky so I punched my program onto paper tape using an off-line ASR-38 teletype that nobody used.  You just turned on the paper tape punch and each character you typed was permanently punched into the tape.  If you made a mistake, there's no back-space per se.  Instead, you pushed a button to go back one character at a time and pressed DEL, which as you all know is all ones.  The paper tape reader would ignore DELs, so it was a way to take care of typos if you noticed them immediately.

Once I had the program on paper tape, I tranferred it to DECtape and edited it using the PDP-11.

An advantage to using the ASR-38 was that I had mixed case comments.  Everybody else WAS STILL WRITING ALL THEIR PROGRAMS IN ALL CAPS LIKE HERMAN HOLLERITH INTENDED so writing mixed case comments made me an outcast among nerds -- like Seymour Cray because he used a circular slide rule.  But then Unix arrived and the world went the other way -- to all lower case.  this was almost equally annoying.  why throw away half of your characters?  mumble mumble random nebbish hackers.

Drew Fustini wrote:

 

At least they do have nice displays of PDP-8 and PDP-11 and a working PDP-1!

Oooh, that's a lovely little high-speed fan-fold paper tape reader!

In the class I mentioned above, you had to sign up for maybe an hour a day on a shared PDP-11, so you had to enter your programs off-line.  Most students used punched cards, but the punched card reader was quirky so I punched my program onto paper tape using an off-line ASR-38 teletype that nobody used.  You just turned on the paper tape punch and each character you typed was permanently punched into the tape.  If you made a mistake, there's no back-space per se.  Instead, you pushed a button to go back one character at a time and pressed DEL, which as you all know is all ones.  The paper tape reader would ignore DELs, so it was a way to take care of typos if you noticed them immediately.

Once I had the program on paper tape, I tranferred it to DECtape and edited it using the PDP-11.

An advantage to using the ASR-38 was that I had mixed case comments.  Everybody else WAS STILL WRITING ALL THEIR PROGRAMS IN ALL CAPS LIKE HERMAN HOLLERITH INTENDED so writing mixed case comments made me an outcast among nerds -- like Seymour Cray because he used a circular slide rule.  But then Unix arrived and the world went the other way -- to all lower case.  this was almost equally annoying.  why throw away half of your characters?  mumble mumble random nebbish hackers.