MCU Deployment Reference

8-bit AVR Family

MCU	Flash	RAM	UART	Mode	Tier	Notes
ATtiny85	8 KB	512 B	USI/SW	No parser	Ultra	Disable parser; feed full LoRa/UDP datagram directly
ATmega48	4 KB	512 B	HW UART0	No parser	Ultra	Only 512 B total RAM; disable parser to fit
ATmega88	8 KB	1 KB	HW UART0	Full parser	Standard	First AVR comfortable with full parser
ATmega168	16 KB	1 KB	HW UART0	Full parser	Standard
ATmega328P	32 KB	2 KB	HW UART0	Full parser	Standard	Arduino Uno/Nano baseline. Recommended entry point.
ATmega32U4	32 KB	2.5 KB	HW UART + USB	Full parser	Standard	USB-CDC: feed bytes from SerialUSB.read()
ATmega2560	256 KB	8 KB	4× HW UART	Full parser	Comfort	Multi-channel: one OSRXParser per UART × 4
ATmega4809	48 KB	6 KB	4× USART	Full parser	Comfort	Arduino Nano Every (megaAVR-0); UPDI programming

Config tiers: Ultra / Tight / Standard / Comfort. See Configuration for macro settings.

32-bit Targets

MCU	Flash	RAM	Mode	Notes
STM32F030F4	16 KB	4 KB	Full parser	Cortex-M0; all APIs fit comfortably
STM32F103C8	64 KB	20 KB	Full parser	Multi-channel receiver; 3× UART available
ESP8266	1–4 MB	80 KB	Full parser	One UDP datagram per osrx_feed_bytes call
ESP32	4 MB	520 KB	Full parser	Preferred LAN gateway platform
RP2040	2 MB	264 KB	Full parser	PIO-based UART; DMA callback into osrx_feed_bytes