DEC H-500 Digital Trainer

[granz]

They don't make them like this any more. Someone actually made a CPU out of several of these - I'll have to dig around for that article.

[Chris Savage]

They don't make them like this any more. Someone actually made a CPU out of several of these - I'll have to dig around for that article.

Very nice! I remember when Parallax sold a Digital Electronics Trainer. It seems like it was discontinued long before most people even knew it was a product. My biggest complaint about Parallax has always been how products are just gone, often with no trace of documentation or support left behind.

But, back on subject, I wish I had something like this (above) when I was learning. It would have made things much easier and I would have learned sooner than later.

[granz]

Very nice! I remember when Parallax sold a Digital Electronics Trainer. It seems like it was discontinued long before most people even knew it was a product. My biggest complaint about Parallax has always been how products are just gone, often with no trace of documentation or support left behind.

Do you happen to have a link to any of the documentation/info on that Parallax trainer? It sounds interesting.

But, back on subject, I wish I had something like this (above) when I was learning. It would have made things much easier and I would have learned sooner than later.

Michael Gardi [mgardi] has built a recreation of this DEC trainer.

https://www.hackster.io/news/recreating-a-vintage-dec-h-500-computer-lab-with-an-arduino-b5f73913b487

[Chris Savage]

Do you happen to have a link to any of the documentation/info on that Parallax trainer? It sounds interesting.

This is what the device looked like (see more below):



Here's a thread about it on the Parallax forums.

The manual can be found here.

[granz]

Very cool, thanks. Kind of cramped, but it covers quite a bit of logic.

I find it interesting that the manual never mentioned the socket for the BS2 IC that is in the lower-left hand corner of the board. It is especially interesting with the fifteen GPIO pins in the lower-right hand corner. I haven't had the time to go through the thread, I'll have to look there.

[granz]

Hmm, nothing in the thread - other than a brief comment asking if the GPIO pins on the right side are to be connected to a Homework Board. But, I don't think that is right - I cannot find the schematic, but the socket on the left side looks too convenient for a BS2 IC.

It would be kind of like my DT-01 Digital Trainer from K and H Products (first photo in http://zappbots.altervista.org/forum/viewtopic.php?f=40&t=327&sid=b1c554ccf4ebad0117ac2ea7d3f2ca94.

One of my earlier upgrades to that was to take my home-brewed Scott Edwards BASIC Stamp clone (https://www.seetron.com/archive/pdf/cft_mnl.pdf) and place it over the logic probe compartment. It was pretty cool, if I do say so myself.

[Chris Savage]

Hmm, nothing in the thread - other than a brief comment asking if the GPIO pins on the right side are to be connected to a Homework Board. But, I don't think that is right - I cannot find the schematic, but the socket on the left side looks too convenient for a BS2 IC.

I believe that socket was for a BS2. You see, there was a student guide written for schools that used that board. It was called, "Elements of Digital Logic". Like everything else, every trace of it has disappeared from the Parallax website. You'd likely have to post a request on their forums asking if someone happens to have a copy.

It would be kind of like my DT-01 Digital Trainer from K and H Products
It was pretty cool, if I do say so myself.

Very nice! Yeah, I never had anything like that growing up. If Radio Shack didn't have it, I couldn't get it. But I did have much of what Radio Shack offered. Forrest M. Mims III was my tutor via his Radio Shack publishing.

[granz]

Very nice! Yeah, I never had anything like that growing up. If Radio Shack didn't have it, I couldn't get it. But I did have much of what Radio Shack offered. Forrest M. Mims III was my tutor via his Radio Shack publishing.

Yeah, I got that when I was teaching at Gateway Technical Institute (when I was in my early thirties, hardly a kid.) My dev work, as a kid, was tearing apart televisions, radios, Christmas lights (made a tic-tac-toe computer out of those in my early teens,) and anything else. I also made frequent (maybe weekly) pilgrimages to our local Radio Shack - often to use their tube tester and purchase tubes (I still remember that the 6GH8A triode/pentode was the one I needed most.)

I still remember going into the store once and seeing a rack with a whole bunch of small packets of integrated circuits. They were from James Electronics (later called Jameco) and each had a single IC, and on the back was a pin-out diagram, these were their "JimPaks". A few years ago, I called Jameco to place an order; while talking to the woman, I mentioned that rack at Radio Shack, and she told me that she started out packaging those JimPaks, and that the women who worked in her department were called the "JimPak Girls". It was a nice little nostalgia moment.

[granz]

Hmm, nothing in the thread - other than a brief comment asking if the GPIO pins on the right side are to be connected to a Homework Board. But, I don't think that is right - I cannot find the schematic, but the socket on the left side looks too convenient for a BS2 IC.

I believe that socket was for a BS2. You see, there was a student guide written for schools that used that board. It was called, "Elements of Digital Logic". Like everything else, every trace of it has disappeared from the Parallax website. You'd likely have to post a request on their forums asking if someone happens to have a copy.

Yeah, that's what I guessed. I didn't word that very well. What I meant was that the socket
just seemed to be conveniently set up to hold a BS2 - the pin sockets on the right seemed to agree with my guess.