Hi,
I've observed that configuring prescaler settings in timers is a common settings. This involves dividing the input clock frequency of the timer. Just to add context, the 32-bit timer's input frequency is 32 MHz.

I'm interested to know how this division contributes to the measurement of longer time intervals, particularly in the context of any microcontrollers or ARM.

Could you please provide some explanations on this?

 

What is your detailed explanation on this?

 

What is your detailed explanation on this?

let me explain

Timer Purpose: In a microcontroller, a timer is a hardware component used to measure or generate time intervals. , it can be configured to measure a specific time interval.

Timer Size: I've chosen a 32-bit timer. This means the timer can count from 0 to a very large number (2^32 - 1), providing a wide range for measuring time intervals.

Clock Source: The timer relies on an external clock source to count time intervals. In this configuration, i uses a clock frequency of 32 MHz. This is the frequency at which the timer's counter increases by 1 with each clock cycle.

I want to know what happens when I set a pre-scaler of 1/4.?

Pre-scaler: set a pre-scaler of 1/4.

 

Hi MT,
Read this PDF clip.
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I want to know what happens when I set a pre-scaler of 1/4.?

The input to the timer is reduced, by dividing by 4, from 32Mhz to 8Mhz

 

I want to know what happens when I set a pre-scaler of 1/4.?

It can count four times as long before it overflows.

 

The input to the timer is reduced, by dividing by 4, from 32Mhz to 8Mhz

I'm interested in understanding how dividing the clock frequency in a timer allows for longer time measurement

 

It can count four times as long before it overflows.

So, setting the maximum preset value will result in a longer time measurement.

 

I'm interested in understanding how dividing the clock frequency in a timer allows for longer time measurement

You have got to be kidding! If you have a counter that counts to 10, how long does that take with a clock pulse every second. How long with a clock pulse every 4 seconds?

 

You have got to be kidding! If you have a counter that counts to 10, how long does that take with a clock pulse every second. How long with a clock pulse every 4 seconds?

Thank you. When we have a counter that counts to 10 and it's driven by a clock pulse every second, it will take 10 seconds to reach its maximum value.

However, if the same counter is driven by a clock pulse every 4 seconds, it will take 40 seconds to reach its maximum value because it only increments every 4 seconds.

 

Just in case it isn't obvious to you, when you use a prescaler it also reduces the timer resolution.
If you're counting 1MHz with a 1:1 prescaler you count in 1us increments.
If you use a 1:4 prescaler then the input clock gets divided by 4, so you now count in 4us increments.

 

Thank you. When we have a counter that counts to 10 and it's driven by a clock pulse every second, it will take 10 seconds to reach its maximum value.

However, if the same counter is driven by a clock pulse every 4 seconds, it will take 40 seconds to reach its maximum value because it only increments every 4 seconds.

So, do you now understand why a pre-scaler allows for longer intervals?

 

So, do you now understand why a pre-scaler allows for longer intervals?

Yes, By making adjustments to the prescale setting, it becomes possible to reach the maximum delay value.