Finding a distinction - microcontrollers vs microprocessors?

Thread Starter

KevinEamon

Joined Apr 9, 2017
261
Hi guys;

I'm doing the literature review part of my project. This involves comparing and contrasting suitable solutions for systems used in the project.

I settled on using a Raspberry PI(RPI) for my design. But I have to write about how I got there.

I want to setup two fields of contention - now I know the RPI is a single board computer. I know it involves the use of a microprocessor.
Something like a texas instruments basic development board - That really uses microcontroller based technology, right?

So is that my distinction? Microcontroller units vs microprocessor devices.

I'm aware of the key features of both, but when I look at technologies on the market, there seems to be a lot of crossover, on marketable solutions.

What I'm looking for is not detailed. I just really want a good solid labels for a distition and maybe a leading contenders from each field.
 

MaxHeadRoom

Joined Jul 18, 2013
19,148
In my book both describe the same thing, if you want to get picky, then a Micro-controller could also be a descrete logic controller, i.e. does not posses a CPU. for e.g.
Basically splitting hairs.
Max.
 

Thread Starter

KevinEamon

Joined Apr 9, 2017
261
Hmmm a discrete logic controller. Perhaps that's it. I have a look but: -

Ok let me say it this way - a single board computer vs what?
See I need this multi threading for all the web communication etc, need the advanced peripheral interfaces like ethernet ports. Needs to be adaptable.

So what's the field of devices called that doesn't have those things? What's the distinction?
 

MaxHeadRoom

Joined Jul 18, 2013
19,148
I would think it also depends on whether your system is completely self contained, IOW, is it a complete (Microcontroller) control system, no real extra peripherals needed.
Seems to me as though you may be getting bogged down by semantics.;)
Max.
 

Thread Starter

KevinEamon

Joined Apr 9, 2017
261
I would agree no doubt. In fact the entire endeavor is an exercise in futility saying as I already have a suitable solution. But the project report is all about the semantics, so I just want to know what they are. I need the thing that has the ability to communicate with the internet, upload data using PHP, accept the inputs from the sensor manipulate the data etc. What is this thing called? And whats the things that don't have all them capabilities called?
 

ronsimpson

Joined Oct 7, 2019
155
The microcontroller once programmed, can work on its own since it has a stored set of instructions that it executes as and when required. A microcontroller can be easily said to be a small microprocessor that has a CPU, RAM, ROM and the input and output ports all embedded on the single microchip.

Microprocessors are normally called what we refer to as a Central Processing Unit

One of my first projects used a 8080 CPU, + external RAM, + external ROM (instructions memory) + external oscillator + ADC + some little parts. Each is a separate IC. (the microprocessor is the IC that does the thinking)

Later on I used Microcontrollers where every thing was in one IC.

I have worked on computers where all the thinking was done on a large board with 100s of ICs. (pre- Microprocessors)

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SamR

Joined Mar 19, 2019
1,293
There is the uP chip THE Microprocessor, the development board has that plus, power regulation, communication interface (USB, I2C, MODbus, etc.), indicator lights, I/O connections (pins, sockets, screw terminals, etc.), frequency oscillator, clock, reset button, etc. It gets called by many names including processor, development board, single-board computer, microcontroller, etc. The Microprocessor is the chip used for the board.
 

WBahn

Joined Mar 31, 2012
24,849
Hi guys;

I'm doing the literature review part of my project. This involves comparing and contrasting suitable solutions for systems used in the project.

I settled on using a Raspberry PI(RPI) for my design. But I have to write about how I got there.

I want to setup two fields of contention - now I know the RPI is a single board computer. I know it involves the use of a microprocessor.
Something like a texas instruments basic development board - That really uses microcontroller based technology, right?

So is that my distinction? Microcontroller units vs microprocessor devices.

I'm aware of the key features of both, but when I look at technologies on the market, there seems to be a lot of crossover, on marketable solutions.

What I'm looking for is not detailed. I just really want a good solid labels for a distition and maybe a leading contenders from each field.
I would say that, from a practical standpoint, microprocessors are more geared toward generic processing of information while microcontrollers are more geared toward interacting with the physical world.

These separate aims account for much of the differences, such as seeing more peripherals on an MCU along with ROM and RAM and limited extensibility, whereas MPUs are intended to be much more general in nature resulting in them being much more extensible via reliance on external RAM and I/O busses.
 

Thread Starter

KevinEamon

Joined Apr 9, 2017
261
Sigh... Ok I think I need to rethink this whole misadventure... I've think I've attempted to construct distinctions that don't exist.
On the other hand I found a journal article use called - the blurry line between microcontrollers and microprocessors - ironically enough :D Thanks guys
 

SamR

Joined Mar 19, 2019
1,293
The absolute definition of a processor has had what we used to refer to as project creep. As chips got smaller and more densely occupied more and more was brought in from their periphery and combined into the chip. A prime example was the 80286 CPU and its 80287 AMU "math coprocessor". Which is now incorporated into the processor instead of as a separate unit.
 

WBahn

Joined Mar 31, 2012
24,849
Sigh... Ok I think I need to rethink this whole misadventure... I've think I've attempted to construct distinctions that don't exist.
On the other hand I found a journal article use called - the blurry line between microcontrollers and microprocessors - ironically enough :D Thanks guys
My guess is that if you went back thirty or forty years you would find that microcontrollers and microprocessors were pretty different critters with certain features that both nearly always had, some features that one almost always had and that the other might or might not have, a number of features that each might or might not have, and features that that one or the other might have but the other seldom had. This was largely driven by microcontrollers usage being driven by one-time-programmed embedded system applications. But, as with lots of things, as the technology improves and evolves each side gains many of the capabilities of the other until you get lots of products that so thoroughly straddle the line that, for them, it becomes pointless to try to classify them as one or the other.
 

MaxHeadRoom

Joined Jul 18, 2013
19,148
And there are many other examples of where the microprocessor has now included what were all once separate logic IC's such as a 40pin USART, A/D convertors, I/O buffers etc.
Max.
 

Thread Starter

KevinEamon

Joined Apr 9, 2017
261
Hi Wbahn;
Missed chatting, my internship was a blur. Never a moment to spare. You were right about the databases being important! I had to design one lol :D Fun times...
One of the elements of our fourth year modules is FPGAs and obviously the history with PLAs etc. So I get what you're saying about reprogrammability and such.
Anyways I've the dreaded literature review nearly finished now, I opted for making the distinctions a little more subtle... ;)
 

nsaspook

Joined Aug 27, 2009
6,473
In the biz end microcontrollers and microprocessors are what the manufacturers decide. Company 'M' , company 'O' and company 'I' don't compete for the same business so they can share and bargain for old equipment on a much nicer level.;)
 
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