SPRUIW9C October 2021 – March 2024 TMS320F280033 , TMS320F280034 , TMS320F280034-Q1 , TMS320F280036-Q1 , TMS320F280036C-Q1 , TMS320F280037 , TMS320F280037-Q1 , TMS320F280037C , TMS320F280037C-Q1 , TMS320F280038-Q1 , TMS320F280038C-Q1 , TMS320F280039 , TMS320F280039-Q1 , TMS320F280039C , TMS320F280039C-Q1
At power-up, the device is clocked from an on-chip 10-MHz oscillator (INTOSC2). INTOSC2 is the primary internal clock source and is the default system clock at reset. It is used to run the boot ROM and can be used as the system clock source for the application. Note that the INTOSC2 frequency tolerance is too loose to meet the timing requirements for CAN. Use of the CAN modules requires an external oscillator. When INTOSC2 is used as the system clock source, GPIO19 (X1) and GPIO18 (X2) are available as GPIO pins.