mc9s08gt16a Freescale Semiconductor, Inc, mc9s08gt16a Datasheet - Page 125

• Manufacturer Part Number: mc9s08gt16a
• Description: Hcs08 Microcontrollers 8-bit Microcontroller Family
• Manufacturer: Freescale Semiconductor, Inc

Chapter 9
Internal Clock Generator (S08ICGV4)
9.1
The MC9S08GT16A/GT8A microcontroller provides one internal clock generation (ICG) module to
create the system bus frequency. All functions described in this section are available on the
MC9S08GT16A/GT8A microcontroller. The EXTAL and XTAL pins share port G bits 2 and 1,
respectively. Analog supply lines V
pins. Electrical parametric data for the ICG may be found in
Freescale Semiconductor
ICG
Introduction
ICGLCLK*
ICGERCLK
FFE
Freescale Semiconductor programs a factory trim value for ICGTRM into
the FLASH location $FFBE (NVICGTRM). Leaving this address for the
ICGTRM value also allows debugger and programmer vendors to perform
a manual trim operation and store the resultant ICGTRM value into
NVICGTRM for users to access at a later time. The value in NVICGTRM
is not automatically loaded and therefore must be copied into ICGTTRM by
user code.
ICGOUT
* ICGLCLK is the alternate BDC clock source for the MC9S08GT16A/GT8A.
CPU
÷
CONTROL
2
SYSTEM
LOGIC
÷
2
FIXED FREQ CLOCK (XCLK)
Figure 9-1. System Clock Distribution Diagram
RTI
BUSCLK
MC9S08GT16A/GT8A Data Sheet, Rev. 1
DDA
and V
BDC
TPM1
SSA
NOTE
are internally derived from the MCU’s V
COP
TPM2
Appendix A, “Electrical
ATD has min and max
frequency requirements. See
Chapter 14, “Analog-to-Digital Convert-
er
“Electrical
(S08ATDV3),” and
IIC1
ATD1
Characteristics.”
SCI1
Appendix A,
RAM
SCI2
Characteristics.”
FLASH has frequency
requirements for program
and erase operation.
See
Characteristics.”
Appendix A, “Electrical
FLASH
DD
SPI1
and V
SS
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