How I learned embedded hardware and firmware - circa 1984

RE: How I learned embedded hardware and firmware - circa 1984

Former Member — Mon, 20 Jan 2014 15:08:51 GMT

My first job as an electronic technologist was to wire wrap a new I/O board for a Data General mini-computer. This was a computer that took up an entire wall in the classroom at the tech institute I was working at. The space was used by the computer, the tape drive, the card reader, and I think a teletype printer of some sort. All that power...and now I have it in my 10" netbook.

RE: How I learned embedded hardware and firmware - circa 1984

packetgeek — Sun, 19 Jan 2014 23:28:30 GMT

Augh! Wire-wrap and sockets (and yes, wire-wrapped sockets) with a S100 bus! Pardon me while I have a shuddering flash-back. My first thought was that the S100 board (shown above) violated a number of spacing guidelines for heat disappation (instructor back then was a retired USMC Drill Instructor and less-than-optimal spacing was a sure-fire way of failing his course). Final lab for a class back then involved using touch circuits to control lights and dial a phone (by pulsing a relay).

Also, I remember the 555 timer fondly.

- Tim

RE: How I learned embedded hardware and firmware - circa 1984

Former Member — Sun, 19 Jan 2014 20:56:58 GMT

Back in the late 70s I ordered a timer from James Electronics (now Jameco). It promised all kinds of possibilities. Now back in those days, catalogs were scarce, there was no internet and no email, so I wasn't really sure WHAT I bought. My timer came in and it was a single 8 pin IC, the venerable 555. What the hell is this? I knew nothing. I expected something with a control knob on it and some kind of display! I started studying, took a correspondence course from National Technical Schools, realized that wasn't enough, quit my high paying job (6 weeks holiday) and went back to school. I was almost disowned by my family for doing such a radical thing. Graduated with honors, 'cause I was so determined (I was 31 years old), got a job in a prep lab for the Instrumentation Department of that same technical school. Then the learning really began! In order to repair student experiments and prepare others for the instructors, I had to learn digital electronics, and began with Motorola development boards, using 6800, 6802, and 6809 MPUs. I loved the stuff, and gobbled it up like a dog with an ice cream cone. Knew most of the assembler codes by heart but always walked around with a programming card in my shirt pocket just in case! What a nerd! I ended up teaching digital electronics and made this my life long hobby. Two years ago I abandoned the old Motorola stuff, and got into Microchip PICs and have been happily programming and making circuit boards ever since. I have the ME Labs LabX1 development system, and the Mikro Elektronika EasyPicV7 development system. I use a USB scope from Parallax. The 555? I made probably 100 circuits with this, but now use 8 pin PICs instead since I can get the same functionality, but all in software. Cool stuff.

I like what you did with the Agilent Mark. that is really cool.

RE: How I learned embedded hardware and firmware - circa 1984

Former Member — Tue, 19 Nov 2013 16:46:19 GMT

Mark, I can still read most of that hex listing without needing to look up the opcodes.. At around that time I was in the same position of not being able to afford an assembler, so I wrote my own assembler/disassembler in hex. The font your printer used looks oddly familiar too [View:/resized-image/__size/16x16/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-0119576d-532e-4986-ad1c-e52d3b3e0be5/contentimage_5F00_1.png:16:16]

I might still have the tape it was saved on somewhere, I have a vague recollection of seeing it a few years ago. Like you I'd have no way of playing it today even if I ever do find it again.

I think todays hobbyist/engineer misses a lot by not having experienced things like this. While the relevance today is less, it's part of that lifetimes worth of experience that you just can't easily obtain any other way. I have some difficulty imagining todays generation sitting down and reading a dead tree version of certain Rodnay Zaks book when they can just get instant google gratification.

RE: How I learned embedded hardware and firmware - circa 1984

fustini — Mon, 18 Nov 2013 22:17:50 GMT

Great post!

RE: How I learned embedded hardware and firmware - circa 1984

Former Member — Mon, 18 Nov 2013 20:41:21 GMT

Hi All , I want to study embedded hardware. Can you give me some recomendation?PLS This is very interesting device.Do you have one???

RE: How I learned embedded hardware and firmware - circa 1984

DAB — Fri, 15 Nov 2013 01:04:01 GMT

Hi Mark,

Nice trip down memory lane.

After playing around with electronics in high school, I went to a two year tech school to get started on a career.

After graduating, I went to work in an Aerospace company where I started working with a PDP 11-20. Finding that I had a knack for programming and a company that subsidized college, I worked to achieve a BS in Computer Engineering. The best of both worlds.

I got involved with my first microprocessor when I purchased a Commodore PET 2001, which I still have for sentimental reasons.

In 1977 I got an opportunity to put a TI9900 microprocessor into a sensing system to demonstrate that it was fast enough to do real time signal processing and advanced signal tracking.

After that success I did a number of projects with 8085, Z-80 and other interesting devices.

I agree that early support tools were non-existant. It is amazing what you can do with an oscilloscope, program listing and a good understanding of system operation flow with I/O pins. It was the best engineering experience of my life. It taught me to fully understand what you wanted to do and be able to predict what happens to everything going on inside the little black chip. You also need to pay attention to detail. It matters.

Anyway, it was nice thinking about all the fun I had in my early years. I am still having fun, but I am working in a whole new environment than when I started.

DAB