C8051F970-A-GM Datasheet, PDF (5/454 Pages) Silicon Laboratories – Low Power Capacitive Sensing MCU with up to 32 kB of Flash

C8051F97x
20. CIP-51 Microcontroller Core ........................................................................................... 165
20.1.Performance .............................................................................................................. 165
20.2.Programming and Debugging Support ...................................................................... 166
20.3.Instruction Set ............................................................................................................ 166
20.3.1.Instruction and CPU Timing............................................................................... 166
20.4.SFR Paging................................................................................................................171
20.5.CPU Core Registers .................................................................................................. 178
21. Direct Memory Access (DMA0)....................................................................................... 188
21.1.DMA0 Architecture..................................................................................................... 189
21.2.DMA0 Arbitration........................................................................................................ 189
21.2.1.DMA0 Memory Access Arbitration..................................................................... 189
21.2.2.DMA0 channel arbitration .................................................................................. 190
21.3.DMA0 Operation in Low Power Modes...................................................................... 190
21.4.Transfer Configuration ...............................................................................................190
21.5.DMA0 Registers......................................................................................................... 191
22. Multiply and Accumulate (MAC0) ................................................................................... 203
22.1.Special Function Registers ........................................................................................204
22.2.Integer and Fractional Math ....................................................................................... 204
22.3.Operating in Multiply and Accumulate Mode ............................................................. 205
22.4.Operating in Multiply Only Mode................................................................................ 205
22.5.MCU mode operation................................................................................................. 206
22.6.DMA mode operation ................................................................................................. 206
22.7. Accumulator 1-Bit Shift Operations........................................................................... 208
22.8.Multi-Bit Shift Accumulator Operation ........................................................................ 209
22.9.Accumulator Alignment (Right Byte Shift).................................................................. 210
22.10.Rounding and Saturation ......................................................................................... 210
22.11.Usage Examples......................................................................................................212
22.11.1.Multiply and Accumulate in Fractional Mode ................................................... 212
22.11.2.Multiply Only in Integer Mode ..........................................................................212
22.11.3.Initializing Memory Block Using DMA0 and MAC0.......................................... 213
22.12.MAC0 Registers....................................................................................................... 214
23. Cyclic Redundancy Check Unit (CRC0)......................................................................... 233
23.1.CRC Algorithm ........................................................................................................... 233
23.2.Preparing for a CRC Calculation................................................................................ 235
23.3.Performing a CRC Calculation................................................................................... 235
23.4.Accessing the CRC0 Result....................................................................................... 235
23.5.CRC0 Bit Reverse Feature ........................................................................................235
23.6.CRC Control Registers .............................................................................................. 236
24. Clocking Sources.............................................................................................................242
24.1.Programmable Precision Internal Oscillator............................................................... 243
24.2.Low Power Internal Oscillator .................................................................................... 243
24.3.External Oscillator Drive Circuit .................................................................................243
24.3.1.External Crystal Mode ....................................................................................... 243
24.3.2.External RC Mode ............................................................................................. 244
24.3.3.External Capacitor Mode ................................................................................... 246
24.3.4.External CMOS Clock Mode.............................................................................. 246
Rev 1.0
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