M68EVB908GB60E Freescale Semiconductor, M68EVB908GB60E Datasheet - Page 115

• Manufacturer Part Number: M68EVB908GB60E
• Description: BOARD EVAL FOR MC9S08GB60
• Manufacturer: Freescale Semiconductor
• Type: MCUr

Specifications of M68EVB908GB60E

• Contents: Module and Misc Hardware
• Processor To Be Evaluated: MC9S08GB
• Data Bus Width: 8 bit
• Interface Type: RS-232
• Silicon Manufacturer: Freescale
• Core Architecture: HCS08
• Core Sub-architecture: HCS08
• Silicon Core Number: MC9S08
• Silicon Family Name: S08GB
• Kit Contents: GB60 Evaluation Kit
• Rohs Compliant: Yes
• For Use With/related Products: MC9S08GB60
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

The clock scheme will be FLL engaged, internal (FEI). So
Solving for N / R gives:
A trim procedure will be required to hone the frequency to exactly 5.4 MHz. An example of the trim
procedure is shown in example #4.
The values needed in each register to set up the desired operation are:
ICGC1 = $28 (%00101000)
ICGC2 = $31 (%00110001)
ICGS1 = $xx
ICGS2 = $xx
ICGFLTLU/L = $xx
ICGTRM = $xx
Freescale Semiconductor
Bit 7
Bit 6
Bit 5
Bits 4:3 CLKS
Bit 2
Bit 1
Bit 0
Bit 7
Bit 6:4 MFD
Bit 3
Bit 2:0 RFD
This is read only except for clearing interrupt flag
This is read only; good idea to read this before performing time critical operations
Not used in this example
Bit 7:0 TRIM
N / R = 10.8 MHz /(243/7 kHz * 64) = 4.86 ; We can choose N = 10 and R = 2.
RANGE
REFS
OSCSTEN 0
LOLRE
LOCRE
f
ICGOUT
0
0
1
01
0
0
0
011 Sets the MFD multiplication factor to 10
0
001 Sets the RFD division factor to ÷2
= (f
Unimplemented or reserved, always reads zero
Configures oscillator for low-frequency range; (don’t care)
Oscillator using crystal or resonator requested (don’t care)
FLL engaged, internal reference clock mode
Disables the oscillator in stop modes
Reserved for Freescale Semiconductor internal use; always write zero
Unimplemented or reserved, always reads zero
Generates an interrupt request on loss of lock
Generates an interrupt request on loss of clock
Only need to write when trimming internal oscillator; done in separate
operation (see example #4)
IRG
MC9S08GB/GT Data Sheet, Rev. 2.3
/ 7) * P * N / R ; P = 64, f
IRG
= 243 kHz
Initialization/Application Information
Eqn. 7-5
Eqn. 7-6
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