The MSP430F1122IDW: It runs at 8 MHz and packs 4 KB of Flash program memory with 256 bytes of RAM — enough for a single-threaded control loop, sensor readout, or low-speed data logging. The 8-channel 10-bit ADC brings analog inputs on-chip, and the integrated brown-out reset, power-on reset, PWM timer, and watchdog timer keep external support chips off the board.
8 MHz clock ceiling.
Memory budget: 4 KB Flash, 256 B RAM
4 KB of Flash (4K x 8 plus 256 bytes of info memory) and 256 bytes of RAM. Firmware must be hand-optimised — no RTOS, no fat libraries.
Package and field-service angle
No fine-pitch QFN or BGA — a rework station with a standard iron and some flux can swap it on a bench or even in a parking lot if you're careful. The 14 I/O pins are accessible on the outer leads, and the wide pitch (1.27 mm) means less risk of bridging during a field repair. If you're stocking a field-repair kit, this is the kind of part that goes in the bag.