The maximum clock frequency of the TM4C1231D5PMT is 80 MHz, but it can be overclocked to 120 MHz with some limitations.
The pin muxing on the TM4C1231D5PMT can be configured using the Pin Mux Utility tool provided by Texas Instruments, or by writing code to configure the registers manually.
The main difference between the TM4C1231D5PMT and the TM4C1230D5PMT is that the TM4C1231D5PMT has a larger flash memory (256 KB vs 128 KB) and more SRAM (32 KB vs 16 KB).
The ADC on the TM4C1231D5PMT can be used by configuring the ADC registers, enabling the ADC clock, and using the ADC API provided by Texas Instruments or by writing custom code to read the ADC values.
Yes, the TM4C1231D5PMT can be used with an operating system like Linux or FreeRTOS, but it requires porting the OS to the specific microcontroller and configuring the peripherals and drivers accordingly.