Allow configuring cpu frequency through the platformio board_build.f_cpu. Fixes the potential bug where someone might try using board_build.f_cpu resulting in an F_CPU that differs from the one actually configured (through LPC_SC->PLL0CFG). F_CPU is used in system/lpc176x/time.h for the delay* functions and is also widely used in projects like Marlin.
Currently only allows 120mhz (LPC1769), 100mhz and 96mhz.
Allow configuring cpu frequency through the platformio
board_build.f_cpu. Fixes the potential bug where someone might try usingboard_build.f_cpuresulting in anF_CPUthat differs from the one actually configured (throughLPC_SC->PLL0CFG).F_CPUis used insystem/lpc176x/time.hfor thedelay*functions and is also widely used in projects like Marlin.Currently only allows 120mhz (LPC1769), 100mhz and 96mhz.