Peripherals and I/O — what's on the die
Sixteen general-purpose I/O pins are available in the 20-TSSOP package. Serial connectivity covers I²C, SPI, and the Universal Serial Interface (USI), which can be configured as either SPI or I²C but not both simultaneously. The USI is a software-driven interface, so throughput is lower than a dedicated hardware SPI module; budget CPU cycles accordingly if you're streaming data at the bus's maximum rate.
Package and footprint — 20-TSSOP
The supplier device package is 20-TSSOP; the land pattern follows standard IPC-7351 for this footprint. No exposed pad — thermal dissipation is through the leads, so keep ambient airflow in mind if running the MCU near its maximum current draw.
It is ROHS3 compliant. For new designs, the MSP430G2xx series remains a supported, current-production line from Texas Instruments.