MC9S12KG128 Datasheet, PDF (99/600 Pages) Freescale Semiconductor, Inc – Microcontrollers

START
Chapter 2 128 Kbyte ECC Flash Module (FTS128K1ECCV1)
Tbus < 1µs?
NO
ALL COMMANDS IMPOSSIBLE
YES
PRDIV8=0 (reset)
OSCILLATOR
CLOCK
NO
> 12.8 MHZ?
YES
PRDIV8=1
PRDCLK=oscillator_clock/8
PRDCLK=oscillator_clock
PRDCLK[MHz]*(5+Tbus[µs]) ^NO
an integer?
YES
FDIV[5:0]=INT(PRDCLK[MHz]*(5+Tbus[µs]))
FDIV[5:0]=PRDCLK[MHz]*(5+Tbus[µs])-1
TRY TO DECREASE Tbus FCLK=(PRDCLK)/(1+FDIV[5:0])
1/FCLK[MHz] + Tbus[µs] > 5
AND
FCLK > 0.15 MHz
?
YES
END
NO
YES
FDIV[5:0] > 4?
NO
ALL COMMANDS IMPOSSIBLE
Figure 2-23. Determination Procedure for PRDIV8 and FDIV Bits
MC9S12KG128 Data Sheet, Rev. 1.15
Freescale Semiconductor
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