Architecture & Selection criteria of an Microcontroller

In Embedded system Architecture of Micro controller(MC) plays very important role as MC is heart of your project/product.

Architecture can be classified as:
8 Bit: 
Eg:8051,Atmel C51,RS08
Application/Features:Small processing,Limited I/O,Cheap,speed Max 30Mhz


16 Bit: 
Eg:ST10,C16X

Application/Features:Automation control,4-32Kb RAM,speed Max 60Mhz

32 Bit:

Eg:ARM ,PIC 32,MIPS 32, Cortex 

Application/Features:32kb-2MBRAM,speed 600Mhz and above.

Selection criteria of an Architecture:

1.Simplicity:Architecture selected should be simple for project/product with respect to Hardware and software design.

2.Peripheral options:Check if this architecture supports future interface devices you plan to integrate.

3.Support/Technical Data: All the required info about this devices should be readily available.

4.Tool chains/Development Environment/Libraries: All software support like tool chain(compiler+assembler+liker+debugger+loader) should be readily available.