What was before microcontrollers ?

[eagle1109]

Hi,

I'm writing a course manual about microcontrollers, and I just need to put a part talking about what was before microcontrollers, to enhance my point of how microcontrollers evolution played a huge role in modern control systems and embedded systems.

I think I read somewhere long time ago that control systems were done with logic gates, combination and sequential integrated circuits. Which means control with non-programmed electronic circuits.

Can anyone provide me with some sources about this particular subject ?

 

[crutschow]

Before digital control systems, there was analog.
Look up analog control systems with PID feedback.
Analog PID is still emulated in digital control systems although other pure digital techniques, such as Fuzzy Logic, are also used.

These analog control systems where mostly mechanical (look up the WWII Norden bombsight) or even hydraulic, before solid-state electronics was developed in the 50's (I suppose to you that's a "long time ago" but not to me ) .
The analog solid-state systems used operational amplifiers to do the PID control.

There was not much digital control of systems until the microcontroller was developed.
They may have used some integrated logic gates, but the PID control was usually still analog.

 

[eagle1109]

before solid-state electronics was developed in the 50's (I suppose to you that's a "long time ago" but not to me ) .

haha, oh yeah I really meant something like a year or couple years at most

Thank you so much for the answer.

Can you point me to a document or a key word to use it a google search to get something about electronic control system hierarchy, roadmap or timeline advancement.

When I use electronic control system, I get results about car ECU which is a totally different subject to what I'm searching for.

 

[Easy peasy]

cmos logic gates - and TTL / RTL were state of the art before uP's

cmos was the breakthru that allowed the 4004 and all the others - no BJT's in uP, hardly ever ...

 

[danadakk]

RTL and DTL and TTL logic predated 1972 release of 4004, first used in a Japanese Calculator.

And PALs / GALs / ROMs used as memory elements to build state machines.

PDP8 minicomputers were being built in mid 1960's.


Regards, Dana.

--- Updated Jul 6, 2022 ---

cmos logic gates - and TTL / RTL were state of the art before uP's

cmos was the breakthru that allowed the 4004 and all the others - no BJT's in uP, hardly ever ...

The 4004 was 10 um PMOS, needed HV clock swings to run it.


Regards, Dana.

 

[eagle1109]

Thank you guys for the answers.

OK, so I know the story about the Japanese calculator. Let say in the 70s or 80s, of course I was a little boy so I even didn't know anything about technology but the TV and the ATARI console.

At that time, of course the microprocessor was the revolution, but many appliances were very basic which didn't have any microcontroller in them. But I think microcontrollers were used in the industry I guess.

I just did a quick search about the ATARI and found this link about ATARI teardown:
https://www.ifixit.com/Teardown/Atari+2600+Teardown/3541

So the ATARI has a CPU not a microcontroller. So I think the microprocessor was maybe the only controller at that time which of course requires the other chips to work with; like, ROM, RAM, timers ... etc.

I searched about the intel 4004, which is a microprocessor.

So I guess pretty much everything was done using microprocessors.

I read this in Wikipedia about TMS1000:

TMS 1000 series[edit]​

The die of a TMS1000
The later TMS 1000 series went on the market in 1974. TI stressed the 4-bit TMS 1000 for use in pre-programmed embedded applications.

A computer-on-a-chip combines the microprocessor core (CPU), memory, and I/O (input/output) lines onto one chip. The computer-on-a-chip patent, called the "microcomputer patent" at the time, U.S. Patent 4,074,351, was awarded to Gary Boone and Michael J. Cochran of TI. Aside from this patent, the standard meaning of microcomputer is a computer using one or more microprocessors as its CPU(s), while the concept defined in the patent is more akin to a microcontroller.

So this one might be the first one to be considered as a microcontroller. So does "computer-on-a-chip" or "system on chip" means it's a microcontroller ?

I know it'd be a long story about how the microcontroller started to be used in electronic system, starting with calculators, then I guess maybe in electronic toys, video games, ... etc.

I read this too:

Partly in response to the existence of the single-chip TMS 1000, Intel developed a computer system on a chip optimized for control applications, the Intel 8048, with commercial parts first shipping in 1977. It combined RAM and ROM on the same chip with a microprocessor. Among numerous applications, this chip would eventually find its way into over one billion PC keyboards. At that time Intel's President, Luke J. Valenter, stated that the microcontroller was one of the most successful products in the company's history, and he expanded the microcontroller division's budget by over 25%.

Yes, the background part in the Wiki page about micrcontrollers has a good story about the early uses of micrcontrollers.

--- Updated Jul 6, 2022 ---

This image too is a nice one listing the models and which one is a microprocessor and which is a microcontroller:

 

[danadakk]

https://www.hp.com/us-en/shop/tech-takes/microcontroller-vs-microprocessor

Regards, Dana.

 

[betwixt]

My introduction to electronics was in the 1950s so I've witnessed the adoption of the transistor even before ICs and microcontrollers were dreamed of.

I think its fair to say that the applications grew up along side the technology, things we now take for granted that rely on microcontrollers simply didn't exist so its wrong to think that some earlier system was used before they were developed.

I think the answer to the question though, is that prior to the large scale integration on silicon, smaller scale was used. I remember computer monitors with 100+ TTL, ECL and DTL ICs on large PCBs and usually a mass of wires soldered to the back to fix the design bugs, even on production models. Then came bit-slice processors, a mix of TTL and what we now call PLDs, they made things far faster and the architectures of modern systems came into being. Then LSI like the devices mentioned earlier arrived and finally, the integration of the peripherals and core processor to make a microcontroller.

Those were the days....

Brian.

 

[crutschow]

cmos was the breakthru that allowed the 4004 and all the others - no BJT's in uP, hardly ever ..

There were some high-speed (for the time) bit-slice processors that were fabricated using bipolar ECL circuits.

So does "computer-on-a-chip" or "system on chip" means it's a microcontroller ?

The difference between a microcontroller and a microprocessor is more one of where they are used, rather than basic design
They both have integrated CPU's that do the control.
A microcontroller for embedded processing and control often has added functions like timers, and A/D and D/A converters included on-chip for interface to the outside world, and usually speed of operation is not greatly emphasized.
Microcomputers usually just have (possible multiple) CPUs, hardware multipliers, and large on-chip cache memory, used for general purpose computing, with an emphasis on speed of processing (note the PC microcomputer speed war between Intel and AMD).

 

[danadakk]

Generally speaking its whether or not memory and peripherals are onchip -

Intel 8048 -

8086 -

Regards, Dana.

 

[wwfeldman]

intel 4004 per IEEE Spectrum, July 2018

Chip Hall of Fame: Intel 4004 Microprocessor

The first CPU-on-a-chip was a shoestring crash project

spectrum.ieee.org

from 50,000 feet:
vacuum tubes
transistors
integrated circuits
processors

as things get smaller, they use less volume and less power

 

[betwixt]

Showing my age: I've got quite a few 'antique' ICs here. I'm missing the rare 4004 which is a pity because it would be fun to make one do something. Multi-core MCU's with WiFi and Bluetooth are great for rapid development and low cost but somehow don't have the appeal of real 'nuts and bolts' technology.

I suppose they really belong in a museum, but then so do I

Brian.

 

[eagle1109]

I think the answer to the question though, is that prior to the large scale integration on silicon, smaller scale was used. I remember computer monitors with 100+ TTL, ECL and DTL ICs on large PCBs and usually a mass of wires soldered to the back to fix the design bugs, even on production models. Then came bit-slice processors, a mix of TTL and what we now call PLDs, they made things far faster and the architectures of modern systems came into being. Then LSI like the devices mentioned earlier arrived and finally, the integration of the peripherals and core processor to make a microcontroller.

Yep, absolutely. Always on point

That's what I meant exactly, that period before microcontrollers, there were a lot of applications and systems, or part of a system which was done using non-programmed chips, and of course this part of a system is built with a lot of ICs to perform a task, which is then one microcontroller can do it easily.

Then, advancement kept going until the introduction of microcontrollers.

What I really want to put in the manual I'm working on, is maybe a little like a motivation section to express the importance and the impact of microcontrollers.

I wanted to collect some text information with some images, but also I like your answer and maybe take some keywords or disassemble the answer and reformulate it as what fit the section in the manual.

Thank you so much,

 

[SakshiVerma]

Microcontrollers are small, low-power computers that are used in a wide variety of applications. They were initially developed as processors for embedded systems, but they have since been adopted for a broader range of uses, including mobile apps and wearables. Today, microcontrollers can be found in various applications, from industrial controls to consumer electronics.