C8051F340-GQR Datasheet, PDF (4/276 Pages) Silicon Laboratories – Full Speed USB Flash MCU Family

C8051F340/1/2/3/4/5/6/7/8/9/A/B/C/D
11.2.Power-Fail Reset / VDD Monitor .................................................................... 102
11.3.External Reset ................................................................................................ 103
11.4.Missing Clock Detector Reset ........................................................................ 103
11.5.Comparator0 Reset ........................................................................................ 103
11.6.PCA Watchdog Timer Reset .......................................................................... 103
11.7.Flash Error Reset ........................................................................................... 103
11.8.Software Reset ............................................................................................... 104
11.9.USB Reset...................................................................................................... 104
12. Flash Memory ....................................................................................................... 107
12.1.Programming The Flash Memory ................................................................... 107
12.1.1.Flash Lock and Key Functions ............................................................... 107
12.1.2.Flash Erase Procedure .......................................................................... 107
12.1.3.Flash Write Procedure ........................................................................... 108
12.2.Non-Volatile Data Storage.............................................................................. 109
12.3.Security Options ............................................................................................. 109
13. External Data Memory Interface and On-Chip XRAM........................................ 114
13.1.Accessing XRAM............................................................................................ 114
13.1.1.16-Bit MOVX Example ........................................................................... 114
13.1.2.8-Bit MOVX Example ............................................................................. 114
13.2.Accessing USB FIFO Space .......................................................................... 115
13.3.Configuring the External Memory Interface .................................................... 116
13.4.Port Configuration........................................................................................... 116
13.5.Multiplexed and Non-multiplexed Selection.................................................... 119
13.5.1.Multiplexed Configuration....................................................................... 119
13.5.2.Non-multiplexed Configuration............................................................... 120
13.6.Memory Mode Selection................................................................................. 120
13.6.1.Internal XRAM Only ............................................................................... 121
13.6.2.Split Mode without Bank Select.............................................................. 121
13.6.3.Split Mode with Bank Select................................................................... 122
13.6.4.External Only.......................................................................................... 122
13.7.Timing .......................................................................................................... 122
13.7.1.Non-multiplexed Mode ........................................................................... 124
13.7.2.Multiplexed Mode ................................................................................... 127
14. Oscillators ............................................................................................................. 131
14.1.Programmable Internal High-Frequency (H-F) Oscillator ............................... 132
14.1.1.Internal H-F Oscillator Suspend Mode ................................................... 132
14.2.Programmable Internal Low-Frequency (L-F) Oscillator ................................ 133
14.2.1.Calibrating the Internal L-F Oscillator..................................................... 133
14.3.External Oscillator Drive Circuit...................................................................... 135
14.3.1.Clocking Timers Directly Through the External Oscillator...................... 135
14.3.2.External Crystal Example....................................................................... 135
14.3.3.External RC Example............................................................................. 136
14.3.4.External Capacitor Example................................................................... 136
14.4.4x Clock Multiplier .......................................................................................... 138
14.5.System and USB Clock Selection .................................................................. 139
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Rev. 1.3