criteria for migrating from 8-Bit to 32-Bit Microcontroller

[vijay s]

16-bit versus 32-bit processors argument

Hey Guys

What are the criteria for migrating from 8-Bit to 32-Bit Microcontroller..
and why 16-Bit is not so popular..

 

[GSM Man]

why 16bit is faster them 32bit

Why do you say 16-bit is not popular. Most of my designs are based on 16-bit processors (PIC24 series).

 

[vijay s]

length of 32 bit word

If u see the total Market i.e., No of Micro controllers Shipped in a year, 8-Bit Micro controllers are ruling the industry, followed by 32-Bit Micro controllers...16-bit micro controllers are less compared to others...

i wanna know why u using 16-bit controllers in ur designs and why people using 32-bit controllers...

actually i faced this question in one interview

 

[mfarooq1]

32-Bit World

I dont see any problem with 16 bit microcontrollers. it depends upon the application. every thing is changing very fast, requirements and design improvments. if 32 bit systems with smaller price diffrence are there then why not to use haveing more freedom and power.

 

[GSM Man]

Re: 32-Bit World

When you look at these numbers you have to consider where the processors are being used. If been involved in this inductry for over 35 years so I've seen a lot of changes - the first processor I designed with was the Intel 8008.

People have been predicting the demise of the 8-bit processor for years. But the reality is that there are a lot of embedded applications that require very small, very low-cost controllers. There are very few 4-bit processor available any longer, and the 8-bitters have taken over the markets once served by them. Look at any electronic device and there's a good chance that there's an '8-banger' in there somewhere, even if only as an I/O controller. The 8-bit processors are likely to maintain the largest market share soley because they can be made smaller and cheaper than 16, 32 or 64 bit devices.

When you look at the number of 32 and 64 bit processor sold, you have to consider that the majority of these are employed in devices like PC's and game consoles. Devices that require significant horsepower. While there are embedded applications that require them, they are not the majority.

This is where 16-bit processors fill the gap. While some companies (like Intel) have abandoned that market, others (like Microchip) have embraced it. I do about 15 designs per year, and I find that for the majority of my applications (mostly remote monitoring and control) 16-bit processors offer faster speeds and larger memories for little or no additional cost over an 8-bitter. I only use 8-bit processors when cost or size is the driving factor, and there's not the need for large amounts of memory or a very fast processor.

 

[bobsanjose]

Re: 32-Bit World

People have been predicting the demise of the 8-bit processor for years. But the reality is that there are a lot of embedded applications that require very small, very low-cost controllers.

Don't forget the simple part. Many 8-bits are very easy to use, no programmers models, no RTOS.... That is why 8-bits will be around for quite a while

When you look at the number of 32 and 64 bit processor sold, you have to consider that the majority of these are employed in devices like PC's and game consoles. Devices that require significant horsepower. While there are embedded applications that require them, they are not the majority.

Not really the majority. There are much more 32-bit devices in Cell-phones than in PCs. There are so many more ARM processors sold each year than x86 devices.

This is where 16-bit processors fill the gap. ---snip---- I only use 8-bit processors when cost or size is the driving factor, and there's not the need for large amounts of memory or a very fast processor.

May be it is just a point of view, but I do not see the gap between 8- and 32-bit that needs to be filled by 16-bit micros. The size of the CPU is pretty much irrelevant using technologies of 180 nm or below. If you look at a current price list from Digikey, you will find a number of 32-bit micros, running at faster frequencies, offering more memory and more peripherals at lower prices than comparable 16-bit micros. I guess that is why 32-bit MCUs are more popular than 16-bit MCUs
A little article listing reasons why to switch to higher end MCUs and also why not is here:
**broken link removed**

IMHO, there is no real need for 16-bit MCUs but there is also no big reason why existing 16-bit applications should be transferred to 32-bit as long as the additional performance that comes pretty much for free is not needed. With the same argument that GSM Man used why taking 16-bit over 8-bit I would start new designs with 32-bit over 8- or 16-bit.

Bob