Samsung C8274X User Manual

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S3C8275X/F8275X/C8278X/F8278X/C8274X/F8274X MICROCONTROLLER 
vii 
Table of Contents 
(Continued)
 
Part II Hardware Descriptions
 
Chapter 7   
Clock Circuit
 
Overview........................................................................................................................................................7-1
 
System Clock Circuit ............................................................................................................................7-1
 
Main Oscillator Circuits .........................................................................................................................7-2
 
Sub Oscillator Circuits ..........................................................................................................................7-2
 
Clock Status During Power-Down Modes ............................................................................................7-3
 
System Clock Control Register (CLKCON) ..........................................................................................7-4
 
Clock Output Control Register (CLOCON)...........................................................................................7-5
 
Oscillator Control Register (OSCCON) ................................................................................................7-6
 
Switching the CPU Clock......................................................................................................................7-7 
Chapter 8    
RESET and Power-Down 
System Reset ................................................................................................................................................8-1
 
Overview ...............................................................................................................................................8-1
 
Normal Mode Reset Operation.............................................................................................................8-1
 
Hardware Reset Values........................................................................................................................8-2
 
Power-Down Modes ......................................................................................................................................8-5
 
Stop Mode ............................................................................................................................................8-5
 
Idle Mode ..............................................................................................................................................8-6 
Chapter 9    
I/O Ports 
Overview........................................................................................................................................................9-1
 
Port Data Registers ..............................................................................................................................9-2
 
port 0.....................................................................................................................................................9-3
 
port 1.....................................................................................................................................................9-7
 
port 2.....................................................................................................................................................9-11
 
port 3.....................................................................................................................................................9-13
 
Port 4 ....................................................................................................................................................9-15
 
Port 5 ....................................................................................................................................................9-17
 
Port 6 ....................................................................................................................................................9-19 
Chapter 10   
Basic Timer 
Overview........................................................................................................................................................10-1
 
Basic Timer Control Register (BTCON) ...............................................................................................10-2
 
Basic Timer Function Description.........................................................................................................10-3