89C5121-SK1 Atmel, 89C5121-SK1 Datasheet - Page 22

• Manufacturer Part Number: 89C5121-SK1
• Description: KIT SMART CARD FOR AT89C5121
• Manufacturer: Atmel
• Type: Smart Cardr

Specifications of 89C5121-SK1

• Contents: Board
• For Use With/related Products: AT89C5121
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Other names: T89C5121-SK1; T89C5121-SK1

Clock Management
Functional Block
Diagram
22
A/T8xC5121
In order to optimize the power consumption and the execution time needed for a specific
task, an internal prescaler feature and a X2 feature have been implemented between
the oscillator and the CPU.
Figure 11. Clock Generation Diagram
If CKRL<>7 then:
If CKRL = 7 then:
XTAL1
XTAL2
F
CLK CPU
F
CLK CPU
–
–
Osc.
=
=
F
Fosc
------------- -
2 x2
OSC
F O SC
-----------------
2 x2
CKRL
7
6
5
4
3
2
1
0
x
---------------------------------- -
2 7 CKRL
2
1
–
1
CKCON0
X2
0
1
F
2
OSC
x2
2(7-CKRL)
1
Prescalor Factor
CKRL = 7
CKRL
0
1
10
12
14
1
2
4
6
8
4164G–SCR–07/06
F
F
CLK_CPU
CLK_Periph