Electronics Introduction

 To safely turn off a Raspberry Pi , do one of these: From the terminal (recommended) Shutdown now sudo shutdown -h now Power off immediately sudo poweroff Halt (stops CPU; usually also powers off) sudo halt With a desktop GUI Click Menu (Raspberry icon) → Shutdown… → Shutdown If it’s frozen Try the “magic SysRq” safe reboot sequence (works only if enabled): Hold Alt + PrintScreen Slowly type: R E I S U B (reboots safely; for shutdown you’d usually still need power control afterward) After shutdown When the Pi finishes shutting down, the green ACT LED stops blinking . Then you can remove power (unless you have a power management board that cuts power automatically).

 In Arduino -land, the “ microcontroller model” is usually determined by which Board (and sometimes Processor) you select in the IDE. If you don’t know what chip is on the board, there are a few reliable ways to find it. 1) The fastest: check Tools → Board (and Tools → Processor ) Connect the board. In Arduino IDE: Tools → Board : pick (or confirm) the board family (Uno, Nano, Mega, ESP32 Dev Module, Pico, etc.) Tools → Processor (only appears for some AVR boards like Nano/Pro Mini): this often directly shows the MCU choice, e.g. ATmega328P vs ATmega168 . If you see a “Processor” submenu, that’s basically your answer. 2) Arduino IDE 2.x: Tools → Get Board Info With the board plugged in and the correct Tools → Port selected: Tools → Get Board Info shows things like board name , VID/PID , and sometimes the identified board profile. This won’t always print the exact MCU model, but it helps you confirm the board family so you can map it to the MCU. 3...