Please note the nin-ictalicised 'corrections' of the quote

The thing with much embedded stuff, though, is that it needs to be very specific to your particular requirements, hardware, constraints, etc - so it's extremely unlikely that anything "ready made" will be an exact fit.

The amount of effort it takes to understand this stuff in sufficient detail to adapt it to your specific needs is usually more than the effort it would have taken to properly understand the problem and solve it yourself.

Similarly, there is good stuff out there, and a load of complete rubbish - again, studying it sufficiently to tell the difference is almost always as much work as doing it from scratch!

Erik

The case where "reference code" MAY have a value is after you have understood and coded the stuff yourself and just can not figure out what that little goof is. At such time you will, typically, have developed enough knowledge to get some value out of the "reference code".

as an example take LCD code:

*a) you copy some "reference code" and maybe make a few modifications and it does not work. After poring over the reference code some wrong things are so stuck in your head that even seing it being wrong looking at the datasheet, you totally miss what it is. So you will spend DAYS with the datasheet and "desperate code fixes" ("desperate code fixes" would will get you fired) till it finally penetrates that "what you know" is wrong.

*b) you read the datasheets, figure it out and code it up correctly, but, for some reason it does not seem to work. Then, and only then, do you dig up (8052/google/whatever) some "reference code" and looking it over, you see that the initilaize is called twice. Ah, you say, let me try this.