I said four to avoid confusion:
Compute worst case: 50 * 2 = 100 and 125/100 is 1.25MHz.
The serial flash interface is configured by the flash second stage when using the SDK to run at an integer divider of
the system clock. All the included second stage boot implementations support a PICO_FLASH_SPI_CLKDIV setting (e.g.
defaulted to 4 in https://github.com/raspberrypi/pico-sdk ... _w25q080.S
to make the default interface speed 125/4 = 31.25MHz). This divider can be overridden by specifying
PICO_FLASH_SPI_CLKDIV in the particular board config header used with the SDK.
Compute worst case: 50 * 2 = 100 and 125/100 is 1.25MHz.
Statistics: Posted by dthacher — Sat Nov 30, 2024 3:54 pm