Goodmorning everyone ,
I was making some considerations on arduino modules which are open source hardware.
In principle everyone could build the same module as Arduino gives designs free of charge on the website.
If someone wants to make a board compatible with the IDE, however, there is the question related to microcontrollers that must be pre-programmed with bootloader.
Here my question, because I was quite experienced with Uno Board with atmega328p, which needs bootloader.
Some of the latest ioT modules (I am refering such as Arduino uno Wifi Rev.2, MKR 1010, NANO BLE) have different microcontroller families such as atmega4809, the D21G18 etc ...
for these modules, making a quick search, it would seem that through the USB port a "programmer" is actually implemented directly on the board and therefore to load the sketches no bootloader is required preloaded on the microcontroller.
Basically I'd like to know:
- if these arduino modules need bootloaders or not for use with IDE (Arduino uno Wifi Rev.2, MKR 1010, NANO BLE)
- in general on which arduino boards a bootloader is preloaded and on which there are "virgin" components without any bootloader.
thanks for your attention