1. I have written code for using on chip high speed oscillator for R5F212L4SNFP MCU for maximum 20Mhz speed. Is below settings & sequence ok? 2. How many nop to be added to get clock stable. currently I have added 4. code void set_system_clock(void) { /* Interrupt disable */ asm("FCLR I"); /* Protect off */ prc0 = 1; /* cpu settings */ cm02 = 0; /* Peripheral function clock does not stop in wait mode */ cm05 = 1; /* XIN clock stops */ cm06 = 0; /* CM16, CM17 enabled */ cm10 = 0; /* Clock operates */ cm11 = 1; /* On-chip feedback resistor disabled */ cm13 = 0; /* Input ports P4_6, P4_7 */ cm14 = 0; /* Low -speed on-chip oscillator on */ cm15 = 1; /* XIN-XOUT drive capacity high */ cm16 = 0; /* System clock division select bits; no division */ cm17 = 0; /* System clock division select bits; no division */ ocd0 = 0; /* Oscillation stop detection function disabled */ ocd1 = 0; /* Oscillation stop detection interrupt disable */ ocd2 = 1; /* Selects on-chip oscillator clock */ ocd3 = 1; /* XIN clock stops */ fra00 = 1; /* High-speed on-chip oscillator on */ fra01 = 1; /* Selects high-speed on-chip oscillator */ fra20 = 0; /* High-speed on-chip oscillator frequency sw itching bits, Divide-by-2 mode */ fra21 = 0; /* High-speed on-chip oscillator frequency sw itching bits, Divide-by-2 mode */ fra22 = 0; /* High-speed on-chip oscillator frequency sw itching bits, Divide-by-2 mode */ /* let clock get stable */ asm ( "nop" ); asm ( "nop" ); asm ( "nop" ); asm ( "nop" ); /* Protect on */ prc0 = 0; /* Interrupt enabled */ asm("FSET I"); } /* functin ends here */ /code
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