For other low level programming, Atmel's AVR Studio and their dev boards are incredibley newcomer friendly. Their source level debugger (with the debug coprocessor) is a miracle.
If you'd like to get into "big iron", Embedded Linux is amazing. Raspberry Pi is a great start (lots of GPIOS programmable from userspace). To get into embedded linux kernel programming, start with a loadable module on the Ras-Pi. Also, build/load your own Ras-Pi kernel.
Other folks suggested the ESP8266 which is also great fun to use.
Edit: Learn C. Lots and lots of C. Embedded dev is almost all C. A teeny bit of ASM, sometimes C++. But almost all of it will be in C.
From there, can decide where your interests might be. To continue with Arduino hardware but without the IDE, I'd recommend _AVR Programming_ https://www.oreilly.com/library/view/make-avr-programming/97...
For other low level programming, Atmel's AVR Studio and their dev boards are incredibley newcomer friendly. Their source level debugger (with the debug coprocessor) is a miracle.
If you'd like to get into "big iron", Embedded Linux is amazing. Raspberry Pi is a great start (lots of GPIOS programmable from userspace). To get into embedded linux kernel programming, start with a loadable module on the Ras-Pi. Also, build/load your own Ras-Pi kernel.
Other folks suggested the ESP8266 which is also great fun to use.
Edit: Learn C. Lots and lots of C. Embedded dev is almost all C. A teeny bit of ASM, sometimes C++. But almost all of it will be in C.