MC912DG128A Motorola, MC912DG128A Datasheet - Page 159

• Manufacturer Part Number: MC912DG128A
• Description: Microcontrollers
• Manufacturer: Motorola

System Clock Frequency Formulae
25-clock
MOTOROLA
NOTE:
See
SLWCLK = EXTALi / ( 2 x SLOW )
SLWCLK = EXTALi
PLLCLK = 2 x EXTALi x (SYNR + 1) / (REFDV + 1)
ECLK = SYSCLK / 2
XCLK = SLWCLK / 2
PCLK = SYSCLK / 2
BCLK
Boolean equations:
SYSCLK = (BCSP & PLLCLK) | (BCSP & BCSS & EXTALi) | (BCSP &
BCSS & SLWCLK)
MCLK = (PCLK & MCS) | (XCLK & MCS)
MSCAN system = (EXTALi & CLKSRC) | (SYSCLK & CLKSRC)
BDM system = (BCLK & CLKSW) | (ECLK & CLKSW)
During limp-home mode PCLK, ECLK, BCLK, MCLK and XCLK are
supplied by VCO (PLLCLK).
1. If SYSCLK is slower than EXTALi (BCSS=1, BCSP=0, SLOW>0), BCLK becomes ECLK.
Figure
1
= EXTALi / 2
18:
Clock Functions
System Clock Frequency Formulae
MC68HC912DT128A Rev 2.0
SLOW = 1,2,..63
SLOW = 0
Clock Functions
159