Memory and I/O budget
The 8 KB RAM handles a couple of UART buffers and a small data table; if you need more than that for frame buffering, watch the RAM ceiling. 39 I/O lines are available on the 48-pin package, which covers a keypad matrix and a few status LEDs without needing a port expander.
Connectivity covers I²C, SPI, SSI, SSP, UART/USART, and IrDA, which covers the common sensor and display interfaces. An 8-channel 10-bit ADC handles analog feedback from potentiometers or current-sense resistors.
