You are right, but their flashchip is only supported up 133mhz. https://www.trustedparts.com/en/part/winbond/W25Q16JVSSIQ%20TR https://www.trustedparts.com/en/

You are right, but their flashchip is only supported up 133mhz. https://www.trustedparts.com/en/part/winbond/W25Q16JVSSIQ%20TR https://www.trustedparts.com/en/part/winbond/W25Q16JVSSIQ%20... The flash chip they are using is only rated to 133mhz, so they are setting the SPI clock divider. in hardware.cpp #ifndef NO_OVERCLOCK // dividing the clock by two ensures we keep the spi transfer to // around 62.5mhz as per the st7789 datasheet when overclocking sm_config_set_clkdiv_int_frac(&c, 2, 1); #endif Learned a new work around for overclocking.