mc68hc908ld60 Freescale Semiconductor, Inc, mc68hc908ld60 Datasheet - Page 103

• Manufacturer Part Number: mc68hc908ld60
• Description: M68hc08 Microcontrollers Microcontroller
• Manufacturer: Freescale Semiconductor, Inc

MC68HC908LD60
Freescale Semiconductor
NOTE:
NOTE:
—
Rev. 1.1
MUL[7:4] — Multiplier Select Bits
The multiplier select bits have built-in protection that prevents them from
being written when the PLL is on (PLLON = 1).
VRS[7:4] — VCO Range Select Bits
The VCO range select bits have built-in protection that prevents them
from being written when the PLL is on (PLLON = 1) and prevents
selection of the VCO clock as the source of the base clock (BCS = 1) if
the VCO range select bits are all clear.
The VCO range select bits must be programmed correctly. Incorrect
programming may result in failure of the PLL to achieve lock.
These read/write bits control the modulo feedback divider that selects
the VCO frequency multiplier, N. A value of $0 in the multiplier select
bits configures the modulo feedback divider the same as a value of
$1. Reset initializes these bits to $6 to give a default multiply value
of 6.
These read/write bits control the hardware center-of-range linear
multiplier L, which controls the hardware center-of-range frequency
f
control register (PCTL) is set. A value of $0 in the VCO range select
bits disables the PLL and clears the BCS bit in the PCTL. Reset
initializes the bits to $6 to give a default range multiply value of 6.
VRS
MUL7:MUL6:MUL5:MUL4
. VRS[7:4] cannot be written when the PLLON bit in the PLL
Table 8-2. VCO Frequency Multiplier (N) Selection
Clock Generator Module (CGM)
0000
0001
0010
0011
1101
1110
1111
VCO Frequency Multiplier (N)
Clock Generator Module (CGM)
13
14
15
1
1
2
3
CGM I/O Registers
Technical Data
103