PC912XDP512F0CALR datasheet(85/1348 Pages) FREESCALE

85 / 1348 page

Chapter 2 Clocks and Reset Generator (S12CRGV6)

MC9S12XDP512 Data Sheet, Rev. 2.21

Freescale Semiconductor

2.3.2.1

CRG Synthesizer Register (SYNR)

The SYNR register controls the multiplication factor of the PLL. If the PLL is on, the count in the loop

divider (SYNR) register effectively multiplies up the PLL clock (PLLCLK) from the reference frequency

by 2 x (SYNR + 1). PLLCLK will not be below the minimum VCO frequency (fSCM).

NOTE

If PLL is selected (PLLSEL=1), Bus Clock = PLLCLK / 2

Bus Clock must not exceed the maximum operating system frequency.

Read: Anytime

Write: Anytime except if PLLSEL = 1

NOTE

Write to this register initializes the lock detector bit and the track detector

bit.

2.3.2.2

CRG Reference Divider Register (REFDV)

The REFDV register provides a ﬁner granularity for the PLL multiplier steps. The count in the reference

divider divides OSCCLK frequency by REFDV + 1.

Read: Anytime

Write: Anytime except when PLLSEL = 1

NOTE

Write to this register initializes the lock detector bit and the track detector

bit.

76543210

SYN5

SYN4

SYN3

SYN2

SYN1

SYN0

Reset

00000000

= Unimplemented or Reserved

Figure 2-4. CRG Synthesizer Register (SYNR)

76543210

REFDV5

REFDV4

REFDV3

REFDV2

REFDV1

REFDV0

Reset

00000000

= Unimplemented or Reserved

Figure 2-5. CRG Reference Divider Register (REFDV)

PLLCLK

2xOSCCLKx

SYNR

()

REFDV

()

------------------------------------

PC912XDP512F0CALR Datasheet(PDF) 85 Page - Freescale Semiconductor, Inc

PC912XDP512F0CALR Datasheet(HTML) 85 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL