The Embedded Way - The volatile keyword in C

[@yashesvii]

I don't know if I should say but I never thought how the volatile keyword will change the context with it's placement! This was really crazy! Thank you!

[@mohamedel-hadidy4844]

to sum it up, the volatile keyword prevents the variable from getting cached Thanks for the awesome explanation

[@wew8820]

no, not really from getting cached. the volatile keyword prevents the compiler from optimising away the variable and subsequent code whose access is controlled by that variable based on what value the variable has during static analysis/compilation. Consider a variable that is of type bool, and is set to 'true'. The compiler will see that and go "ok, I can just delete any code that would only be reached if this were false, because this is always going to be true". With volatile you tell the compiler "we don't know what this value will be at runtime, so don't be overly aggressive with your optimisation here, just leave it as is. the variable can change at any time during runtime, it's volatile, it's subject to change without notice"

[@casalaamericana5578]

Direct to "my favorites" list

[@sageeuthanasia9324]

You are a real code guru 😮 Thank you!

[@JoseGonzalez-rt5fk]

Fantastic; it's great explanation of C++ features that are usually shoved in the back. I love your video!

[@iamsuperwen]

please talk about the keyword const, thanks for all the nice educational videos!!

[@MalamIbnMalam]

Is there an embedded course that Siemens has anywhere online?

[@topGfanboy]

So simply explained

[@madhavjha92]

I need to learn embedded programming from scratch.... could you please help

[@rogerthat365]

Hoping my question is not stupid. //program 1 volatile int *x = new int; *x = 5; write(anybinaryfile, &x, sizeof(int*)); while(1); //program 2 volatile int *y; read(anybinaryfile, &x, sizeof(int*)); printf("%d", *y); /* should this work??? if run program 2 before shutting program 1. As when I tried to run program 2, it returned core dump. */

[@jordantaylor2437]

Excellent video, thanks!

[@Darieee]

thanks !!

[@snjkmr055]

Just awesome..........

[@viktorstanchev6567]

Really well explained!

[@aliakv1364]

Very helpfull. Thanks a lot

[@VolkansSpace]

hi from Turkey :) thanks for video

[@cfoch3]

Awesome, thank you.

[@dragosmakovei]

new subscriber!

[@rutvijjoshi8160]

No hesitation in hitting subscribe button

[@kenyquispecondori808]

gracias por la información

[@gghhff3344]

shared variable with another executable thread can be either global or external variable ? is am i right ? is there any more situation ? thank you so much

[@EmbeddedSoftware]

Global and external are the same thing in C. Great care is needed when sharing variables between threads, as there must be atomic access. Better to use RTOS inter-task communication facilities.

[@playFootball100]

Lucid. Thanks a lot.

[@dannyfung9936]

Thk you so much! Thx., pls be more vedio

[@shirishu.deshpande4790]

Looking for embedded job

[@koderkev42]

2x speed

[@espritgaronne9975]

hum! Many Thx

[@madhavjha92]

Hi sir