How to configure for external HXT source?
Posted: 07 Jun 2019, 20:52
Hi,
I need to clock my M484 with an external 12MHz clock source, instead of a 12MHz crystal. I tried the settings as in the RM: programmed '0' to CONIFIG0[27] (FMC) and SYS->GPF_MFPL &= ~(SYS_GPF_MFPL_PF2MFP_Msk | SYS_GPF_MFPL_PF3MFP_Msk) to set the GPIO mode. However, at the clock init stage the CLK->STATUS never indicates the HTX stable, also when trying to enable HSUSBD PHY (HSUSBD_Open()), it dead loops forever.
The 12MHz has been check clean with a DSO and if I bypass the CLK->STATUS the 192MHz PLL seems to work ok by an LED flashing test, although the HSUSBD still refuses to work.
Any clue? or better a sample code supporting the "external clock mode"?
Regards,
David
I need to clock my M484 with an external 12MHz clock source, instead of a 12MHz crystal. I tried the settings as in the RM: programmed '0' to CONIFIG0[27] (FMC) and SYS->GPF_MFPL &= ~(SYS_GPF_MFPL_PF2MFP_Msk | SYS_GPF_MFPL_PF3MFP_Msk) to set the GPIO mode. However, at the clock init stage the CLK->STATUS never indicates the HTX stable, also when trying to enable HSUSBD PHY (HSUSBD_Open()), it dead loops forever.
The 12MHz has been check clean with a DSO and if I bypass the CLK->STATUS the 192MHz PLL seems to work ok by an LED flashing test, although the HSUSBD still refuses to work.
Any clue? or better a sample code supporting the "external clock mode"?
Regards,
David