Guys, I have a strange behavior here.
I follow the guide to set the CPU to 80MHz
, only using different settings in boards.txt, restarting the IDE each time, having correct multipliers for RCC
Code: Select all
#define BOARD_RCC_PLLMUL RCC_PLLMUL_12
#define BOARD_RCC_PLLMUL RCC_PLLMUL_11
#define BOARD_RCC_PLLMUL RCC_PLLMUL_10
#define BOARD_RCC_PLLMUL RCC_PLLMUL_9
#define BOARD_RCC_PLLMUL RCC_PLLMUL_8
#define BOARD_RCC_PLLMUL RCC_PLLMUL_7
#define BOARD_RCC_PLLMUL RCC_PLLMUL_6
The SPI clock frequency is settled to 20 MHz
I set the CPU back to 72 MHz
. The SPI goes to 36 MHz
I set the CPU to 88 MHz
, SPI -> 22 MHz
So with any CPU clock above 72MHz will get an SPI clock set only to half of the expected one. I assume the CPU is also running with half of the expected frequency.
Flash wait states was set to 2.
What a hell is going on here?