Silicon Laboratories C8051F120 Manual page 5

14.7. Watchdog Timer Reset ..................................................................................................169
14.7.1. Enable/Reset WDT ..............................................................................................169
14.7.2. Disable WDT .......................................................................................................170
14.7.3. Disable WDT Lockout.........................................................................................170
14.7.4. Setting WDT Interval...........................................................................................170
15. OSCILLATORS...................................................................................................................173
15.1.Programmable Internal Oscillator .................................................................................173
15.2.External Oscillator Drive Circuit...................................................................................175
15.3.System Clock Selection.................................................................................................175
15.4. External Crystal Example..............................................................................................177
15.5.External RC Example ....................................................................................................177
15.6. External Capacitor Example..........................................................................................177
15.7. Phase-Locked Loop (PLL) ............................................................................................178
15.7.1. PLL Input Clock and Pre-divider.........................................................................178
15.7.2. PLL Multiplication and Output Clock .................................................................178
15.7.3. Powering on and Initializing the PLL..................................................................179
16. FLASH MEMORY ..............................................................................................................185
16.1.Programming The Flash Memory .................................................................................185
16.1.1. Non-volatile Data Storage ...................................................................................185
16.1.2. Erasing FLASH Pages From Software ................................................................186
16.1.3. Writing FLASH Memory From Software ...........................................................187
16.2. Security Options ............................................................................................................188
17. BRANCH TARGET CACHE.............................................................................................193
17.1.Cache and Prefetch Operation .......................................................................................193
17.2.Cache and Prefetch Optimization..................................................................................194
18. EXTERNAL DATA MEMORY INTERFACE AND ON-CHIP XRAM.......................199
18.1.Accessing XRAM..........................................................................................................199
18.1.1. 16-Bit MOVX Example.......................................................................................199
18.1.2. 8-Bit MOVX Example.........................................................................................199
18.2. Configuring the External Memory Interface .................................................................199
18.3.Port Selection and Configuration ..................................................................................200
18.4. Multiplexed and Non-multiplexed Selection.................................................................202
18.4.1. Multiplexed Configuration ..................................................................................202
18.4.2. Non-multiplexed Configuration...........................................................................203
18.5. Memory Mode Selection ...............................................................................................204
18.5.1. Internal XRAM Only ...........................................................................................204
18.5.2. Split Mode without Bank Select ..........................................................................204
18.5.3. Split Mode with Bank Select ...............................................................................205
18.5.4. External Only .......................................................................................................205
18.6. Timing .......................................................................................................................206
18.6.1. Non-multiplexed Mode........................................................................................207
18.6.1.1. 16-bit MOVX: EMI0CF[4:2] = '101', '110', or '111'................................207
18.6.1.2. 8-bit MOVX without Bank Select: EMI0CF[4:2] = '101' or '111'............208
18.6.1.3. 8-bit MOVX with Bank Select: EMI0CF[4:2] = '110'. ..............................209
18.6.2. Multiplexed Mode................................................................................................210
C8051F120/1/2/3/4/5/6/7
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