External clocking STM32F4

[A319]

Hi,

I'm trying to source my board by a external oscillator. In the beginning I accidentally misconcepted this and put an 0.8Vpp on my board. This did not work because my STM32F429 expects a higher level. So I've patched my board and put a CMOS level VCXO on my board which I still had available. But my board still doesn't boot.

What I have configured (Full source of mcuconf.h)

Code: Select all

#define STM32_HSE_ENABLED                   TRUE
#define STM32_LSE_ENABLED                   FALSE
#define STM32_CLOCK48_REQUIRED              FALSE
#define STM32_SW                            STM32_SW_PLL
#define STM32_PLLSRC                        STM32_PLLSRC_HSE
#define STM32_PLLM_VALUE                    20
#define STM32_PLLN_VALUE                    360
#define STM32_PLLP_VALUE                    8
#define STM32_PLLQ_VALUE                    7   

I can check the activity of my code by a LED which I let blink with a virtual timer continuously in my main routine. The internal clock however works, just not the external clock.

Input clock (Probe directly at OSC_IN pin, OSC_OUT floating)

Regards Sven

[Giovanni]

Hi,

Is STM32_HSE_BYPASS defined in your board.h?

Giovanni

[A319]

Hi Giovanni,

No, I haven't. But the external clock still doesn't work.

board.h

Code: Select all

#if !defined(STM32_HSECLK)
#define STM32_HSECLK                20000000U
#endif

#define STM32_HSE_BYPASS

Sven

[Giovanni]

No idea, prebably it is an HW issue because it works on other boards, are you injecting on the right pin? is the pin programmed as expected?

Giovanni

[A319]

Hi Giovanni,

Checking the pins again and again is every time a good answer. The pin is connected to the OSC32_IN not to OSC_IN

Regards Sven