The maximum clock frequency of the MSP430F2350IRHAR is 16 MHz.
To configure the MSP430F2350IRHAR to use an external crystal oscillator, connect the crystal to the XIN and XOUT pins, and set the FLLUNLOCK bit in the FLL_CTL0 register to 1. Then, set the XT2OFF bit in the SYS_CTL register to 0 to enable the external crystal oscillator.
The RST/NMI pin on the MSP430F2350IRHAR is a dual-function pin that can be used as either a reset input (RST) or a non-maskable interrupt (NMI) input. When configured as a reset input, it can be used to reset the device. When configured as an NMI input, it can be used to generate an interrupt that cannot be masked by the interrupt mask register.
To use the built-in UART on the MSP430F2350IRHAR, configure the UART module by setting the UART control registers (UCTL0 and UCTL1) to enable the UART and set the baud rate. Then, use the UART transmit and receive registers (TXBUF and RXBUF) to send and receive data.
The power consumption of the MSP430F2350IRHAR in low-power mode (LPM3) is approximately 0.5 μA/MHz, depending on the clock frequency and the configuration of the device.