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