MC9S12C128V1 Datasheet, PDF (522/690 Pages) Freescale Semiconductor, Inc – MC9S12C Family MC9S12GC Family Reference Manual

Chapter 18 32 Kbyte Flash Module (S12FTS32KV1)
START
Tbus < 1ms?
no
ALL COMMANDS IMPOSSIBLE
yes
PRDIV8=0 (reset)
oscillator_clock
no
12.8MHz?
yes
PRDIV8=1
PRDCLK=oscillator_clock/8
PRDCLK=oscillator_clock
PRDCLK[MHz]*(5+Tbus[ms]) ^no
an integer?
yes
FDIV[5:0]=INT(PRDCLK[MHz]*(5+Tbus[ms]))
FDIV[5:0]=PRDCLK[MHz]*(5+Tbus[ms])-1
TRY TO DECREASE Tbus FCLK=(PRDCLK)/(1+FDIV[5:0])
yes
1/FCLK[MHz] + Tbus[ms] > 5
AND
END
FCLK > 0.15MHz
?
no
yes
FDIV[5:0] > 4?
no
ALL COMMANDS IMPOSSIBLE
Figure 18-21. PRDIV8 and FDIV Bits Determination Procedure
522
MC9S12C-Family / MC9S12GC-Family
Freescale Semiconductor
Rev 01.24