SPRUIZ1B July 2023 – August 2024 TMS320F28P650DH , TMS320F28P650DK , TMS320F28P650SH , TMS320F28P650SK , TMS320F28P659DH-Q1 , TMS320F28P659DK-Q1 , TMS320F28P659SH-Q1
It is sometimes necessary to observe a clock directly for debug and testing purposes. The external clock output (XCLKOUT) feature supports this by connecting a clock to external pins, GPIO73 and GPIO224. The available clock sources are PLLSYSCLK, PLLRAWCLK, CPU1.SYSCLK, AUXPLLRAWCLK, CPU2.SYSCLK, INTOSC1, and INTOSC2.
To use XCLKOUT, first select the clock source using the CLKSRCCTL3 register. Next, select the desired output divider using the XCLKOUTDIVSEL register. Finally, connect either GPIO73 or GPIO224 to mux channel 3 using the GPIO configuration registers.