MC9S12E32CFU FREESCALE [Freescale Semiconductor, Inc], MC9S12E32CFU Datasheet - Page 104

• Manufacturer Part Number: MC9S12E32CFU
• Description: HCS12 Microcontrollers
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Chapter 2 128 Kbyte Flash Module (FTS128K1V1)
104
TRY TO DECREASE Tbus
Figure 2-21. PRDIV8 and FDIV Bits Determination Procedure
FDIV[5:0]=PRDCLK[MHz]*(5+Tbus[ s])-1
yes
ALL COMMANDS IMPOSSIBLE
FCLK=(PRDCLK)/(1+FDIV[5:0])
PRDCLK[MHz]*(5+Tbus[ s])
1/FCLK[MHz] + Tbus[ s] > 5
PRDCLK=oscillator_clock/8
MC9S12E128 Data Sheet, Rev. 1.07
PRDIV8=0 (reset)
FCLK > 0.15MHz
oscillator_clock
FDIV[5:0] > 4?
Tbus < 1 s?
an integer?
PRDIV8=1
START
12.8MHz?
AND
?
yes
yes
yes
no
no
no
no
PRDCLK=oscillator_clock
no
yes
FDIV[5:0]=INT(PRDCLK[MHz]*(5+Tbus[ s]))
ALL COMMANDS IMPOSSIBLE
END
Freescale Semiconductor