The maximum clock frequency for the MSP430F2012TN is 16 MHz, but it can be overclocked up to 20 MHz with reduced reliability and increased power consumption.
To use an external crystal oscillator, connect the crystal to the XIN and XOUT pins, and configure the UCSCTL6 register to select the external clock source. Also, ensure that the MCLK frequency is set to the desired frequency using the UCSCTL1 register.
The minimum voltage required for the MSP430F2012TN to operate is 1.8V, but it is recommended to operate at a minimum of 2.2V for reliable operation.
To use the built-in UART module, configure the UCAxCTL0 register to enable the UART, set the baud rate using the UCAxBR0 and UCAxBR1 registers, and use the UCAxTXBUF and UCAxRXBUF registers to transmit and receive data.
No, the MSP430F2012TN is not 5V tolerant and should not be used with a 5V power supply. The maximum recommended voltage is 3.6V.
MSP430F2012TN datasheet
by Texas Instruments
