mc68hc912d60c Freescale Semiconductor, Inc, mc68hc912d60c Datasheet - Page 427

• Manufacturer Part Number: mc68hc912d60c
• Description: Hc12 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Technical Data — MC68HC912D60A
21.1 Contents
21.2 Introduction
21.3 Practical Aspects For The PLL Usage
21.3.1 Synthesized Bus Frequency
MC68HC912D60A — Rev. 3.1
Freescale Semiconductor
NOTE:
Section 21. Appendix: CGM Practical Aspects
21.2
21.3
21.4
This sections provides useful and practical pieces of information
concerning the implementation of the CGM module.
Starting from a ceramic resonator or quartz crystal frequency F
‘refdv’ and ‘synr’ are the decimal content of the REFDV and SYNR
registers respectively, then the MCU bus frequency will simply be:
It is not allowed to synthesize a bus frequency that is lower than the
crystal frequency, as the correct functioning of some internal
Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 427
Printed Circuit Board Guidelines. . . . . . . . . . . . . . . . . . . . . . . 433
Practical Aspects For The PLL Usage . . . . . . . . . . . . . . . . . . 427
Appendix: CGM Practical Aspects
F
BUS
=
synr
refdv
F
VCO
∈
∈
{
=
{
0,1,2,3...63}
0,1,2,3...7}
F
----------------------------------------------- -
XTAL
(
refdv
⋅
(
synr
+
1
)
+
1
)
Technical Data
XTAL
, if
427