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Embedded programming is antithetical to pretty much every programming trend of the last 20 years. Note: If you are programming on a board that runs Linux or Android then this discussion is not really aimed at you.
Deeply embedded systems are often built on severely resource constrained hardware. The typical embedded system uses only the memory built into the processor which can be a lot less than you expect. Cortex M0 processers for example come in variants with as little as 32KB FLASH and 2 KB RAM. Note the K vs M.
The primary embedded programming languages is C (not C++ even though your compiler will claim to be C/C++). You will also need assembly code if you do board support packages. If you are not a proficient C coder, then get a good book and teach yourself.
Book recommendations: All of these are older than dirt, but they are classics for a reason and will help you develop the mindset of an effective embedded programmer. Some of these are available as free downloads.
* "Practical C Programming" by Steve Oualline for learning C coding in general.
* "The Art of Embedded Systems" by Jack Gansslle for the general philosophy of embedded programming.
* "Math Toolkit for Real-Time Programming" by Jack Crenshaw for complicated math.
* "Insiders Guide to the Phillips ARM7 based Microcontrollers" by Trevor Martin for using processor resources.
Martin's book on Philips ARM7 is the very best hardware tutorial book I have ever read. Hitex did a great thing for embedded programmers when they released this book as a free download (I think Philips paid for this book). I wish they had done the same thing for Cortex M processors, but life happens and money is not infinite.
https://perswww.kuleuven.be/~u0068190/ARM7/lpc-ARM-book_srn.pdf
Embedded systems can go years between reboots and memory usage management is up to the programmer. Automatic memory allocation (malloc, new, etc.), or anything object oriented can be dangerous. Be wary of any library code that uses these kinds of things. This is one of the reasons why I want the source code for all libraries I use.
Ring buffers are your friend. If properly implemented, buffer overflow exploits just became a thing of the past. You will need to be able to deal with missing data. I use packetized messages with error detection and missing message detection built into the communication protocol (I have been using my own processor to processor packetized protocol that I have used and extended over the last 2 decades).
Every embedded product needs a robust powerup self test function. Run a checksum on your application, perform whatever hardware testing you can and protect your non-volatile memory. Break NVM up into structs that fit within your EEPROM page size. Include a non-zero ID value and checksum in each NVM struct. Add limit tests on multiple choice variables, do anything you can do to detect corrupted NVM data since this is a major risk vector for your code. Alert users as best you can when you detect a problem. Always use the enable pin on EEPROMs (don't just tie them to ground). In some EEPROM devices a single bit change (ESD anyone) can turn a read into a write or erase.
Fight to include an LED the user can see for status display, even if you have an operator display. The happy state is best indicated by a slowly flashing (not a solid on or worse, solid off). You can change the flash rate to indicate different status or mode conditions. Pulsed patterns can be used to indicate specific states or error conditions. And don't use a hardware counter/timer to pulse the LED. Put the LED code in the lowest priority (background) task and make it look at variables in each of the other tasks that indicate if the task is hung up.
Embedded systems often directly control hardware. An electrical engineering background really helps. At a minimum, you need to be able to understand an electronic schematic. If you lack this background then I suggest you take some EE classes. Focus on serial interfaces like I2C and SPI. You will also find yourself using UARTs far more than you ever expected. Martin's Philips ARM7 book is a great resource for best to do this kind of stuff.
You will also sometimes have to meet hard real time requirements which are most easily implemented with an RTOS. If there are any hard real time requirements, then start your designs on the RTOS of your choice, because systems inevitably get more complex over time and porting an existing project to an RTOS is a complete waste of time.
F.Y.I. I am very experience using the Nordic Semi SDK and all I can say, this is not a good resource to learn how to do embedded programming. The SDK was designed to work with a wide variety of ARM processors with a minimum of rewriting and the stuff that actually does the work are extremely well hidden and it is difficult to comprehend by reading the tutorial code in the SDK. The SDK is also extremely inefficient (6 nested subroutine calls to toggle a GPIO bit???). The first project I did using this SDK was reading a high speed ADC over a wireless link (5000 reads per second). It turned out I could read the ADC using a bit-bang implementation of the SPI port 3 times faster than the SDK could using the processor's hardware SPI port. That is pretty pathetic.
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Another great performer has checked out. I warmly recommend you to find any of his duets with Lady Gaga (e.g: The Lady is a Tramp). An unexpected and amazing cooperation across generations.
"If we don't change direction, we'll end up where we're going"
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I understand he also - while serving in a segregated military - got demoted essentially for fraternizing with black troops, and assigned to corpse duty (exhuming mass graves for soldiers bodies to send home) as punishment.
It didn't stop him. Later he'd march with MLK Jr.
A real mensch.
Check out my IoT graphics library here:
https://honeythecodewitch.com/gfx
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They have thrown out the playlist and are spinning and talking about Tony.
JAZZ.FM91 - Discover Music
"Mistakes are prevented by Experience. Experience is gained by making mistakes."
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Never was a fan but he had talent. R.I.P.
Give me coffee to change the things I can and wine for those I can not!
PartsBin an Electronics Part Organizer - Release Version 1.1.0 JaxCoder.com
Latest Article: Simon Says, A Child's Game
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Didn't know a lot of his stuff, but surviving in that business for 70+ years, he obviously had a great deal of talent. ![Rose | [Rose]](https://codeproject.global.ssl.fastly.net/script/Forums/Images/rose.gif)
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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Had a question today related to Visual Studio 2013 and I remembered it was still installed on this computer (though I use 2022 these days).
So I tried to run it and it complained that my community edition licence had expired, did I want a new one? "Yes please" I reply. "Sod off" said VS. "I can't get you one".
So I google, and it happened because I stopped using it, and to get it back I'd have to update it to patch 5, and then do this, and that, yada yada yada.
I'll uninstall it. Get the space back! It takes 20 minutes to uninstall, and I'm presented with a dialog:
Setup completed!
All specified components have ben uninstalled successfully.
The computer needs to be restarted before starting the product.
Restart now
So you want to restart the computer to run the app you just removed? 
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
modified 21-Jul-23 8:52am.
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That's because it updated the spyware used to track you during the uninstallation process. All hail Microsoft. 
Jeremy Falcon
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Gee Whiz Jeremy -- one might think you don't completely trust Microsoft!
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Ha ha ha. Guilty. 
Jeremy Falcon
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I often wonder how MS manages so many products
I had a MS Security Essentials update that kept trying to install
after it installed twice OK So I said HIDE this update that did not work
Like a NumNut I contacted MS Support we played the Update OS Game
Yes I am still running Windows 7 65 bit but MS Security is still updating
One tech that I think know what he was doing we did
sfc/scannnow
DISM.exe
chkdsk/f C:
NO Results message was 98 reparse records
Second Contact with MS Support I was told to update to Widows 10
and that updates for MS Security Essentials were not supported
Thank You Very Much I leave the room now
Still get MS Security Essentials updates
I guess it is still working Waiting on Windows 12 ?
Guess one department does not talk to other departments NO SURPRISE
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Quote: Windows 7 65 bit
Well there's your problem, there's an extra bit there. 
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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Where is my scapulae need to remove that bit
Proof Reading Skills are slipping
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An easy one after yesterday's
Useful sounding cover is quite the opposite (8)
In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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I see what you did there! 
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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OK. since it's so quiet ... I'll take it.
Useful handy
sounding HANDI
cover CAP
is quite the opposite
HANDICAP
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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I think everyone else knocked off early ... 
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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Strangely enough I thought of (H)Andy Capp, but my brain stopped there.
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Must try harder Richard
In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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Yes I know that, Pete. But I do find it odd that I can usually complete at least half of The Spectator crossword in a couple of hours, but very rarely get the CCC.
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The Spectator clues are probably well written compared to our amateurish efforts
In a closed society where everybody's guilty, the only crime is getting caught. In a world of thieves, the only final sin is stupidity. - Hunter S Thompson - RIP
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Possibly, but many of the CCC ones are very clever.
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