[General] How to choose MCU

Hi everyone ,
I am in a blind alley , I do not know what i should do
My topic is not releated to which mcu is best , it is releated to how we should choice correct mcu

I am working on robotic for one years , I have some attend to join robotic competition .
Every mcu has different proreprty . High clock frequency , low power consumption , number of special pin (uart,i2c etc)
I used Arduino on my robot and They are not stable .(Sometimes fine , sometimes bad)
I used PIC , MSP430 , CC430 before .I am trying to learn ARM
PIC is cheap , MSP consume very low power , ARM has huge clock speed

Such as in my robot There are 8 analog input pin ,4 pwm output ,2 digital output pin . For more accurate result , Need higher clock frequency but How much ?
Maybe , I am thinking inside the box , because there are alot of external factor for high performance . I released that The coding has huge important position when i used PID feedback algortihm

Briefly, which criterion should i consider when choice mcu ?

Thanks for your help

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For more accurate result , Need higher clock frequency but How much ?...

Click to expand...

that cannot be.

first you write,
*what are your requirements.?
*what are the controllers that meets them?

*check their availability and cost.
*in addition , you should survey on the tools for that controller u have chosen.
*what is its(tools) cost ?(free or other)

*make a judicious choice on the controller based on your requirement and not on other factors.

What is the role of clock speed in robotic ? I know something but I am not competent .
i am student because of that ,i do not have huge budget . It is nearly 100 dollars per robot
I am using QTR-8A Reflectance Sensor , L298N motor driver

'clock' of the controller specify how fast the instructions are executed.

may be , you are mixing manythings and assume that high clock means high accuracy.

In general the ARM-based architectures due to its 32bit data bus, it can comfortably attend to the most varied applications related to general processing and PID control. If you don’t have enough knowing to determine precisely the time requirements of the design, I strongly recommend you consider using this. Concerning to the peripherals, you can make a search either on manufacturer’s webpage or suppliers to find someone that can fit to the amount of built-in hardware modules that you need.

Thank you for your interest ,
Arm takes my attention so much , Probably i used ARM and TI some products
Which arm series is suitable for new to arm ?
According to me , ARM Cortex-M4

Maybe the frdm-kl46z from freescale could be something for you.
If you are using it for a Robot, it may have intersting Features for you, like accelerometer,
magnetometer, light sensor. The proc is a arm0, but depending on what you want to do it should be fast enough for a lot of applications. And it consumes very little power.