Using the MCU to generate the 27Mhz clock for the AT7456E

[Jorropo]

Is your feature request related to a problem? Please describe

I am trying to remove the 27Mhz XO or crystal for the Analog circuit to simplify the BOM and gain mm² on the board.

Describe the solution you'd like

I have tried using PWM with a DMA ring buffer to average 27Mhz, it works but there is 12.5% skew on some ticks and it is too much and does not work.

Describe alternatives you've considered

We could set a PLL to 27 (or 54) Mhz or some multiple and use a PWM peripheral to divide the PLL generated clock down it would probably work.
Altho finding a way to share the PLL with other pieces of code (or finding a free one) might not be practical.

Other information

It might be that this is too inconvenient (require down-clocking the MCU) to be maintained in the codebase.

[Jorropo]

Well we can just do the inverse.