C8051T630 Datasheet, PDF (5/221 Pages) Silicon Laboratories – Mixed-Signal Byte-Programmable EPROM MCU

C8051T630/1/2/3/4/5
20.3. Priority Crossbar Decoder ............................................................................. 114
20.4. Port I/O Initialization ...................................................................................... 116
20.5. Port Match ..................................................................................................... 118
20.6. Special Function Registers for Accessing and Configuring Port I/O ............. 121
21. SMBus................................................................................................................... 127
21.1. Supporting Documents .................................................................................. 128
21.2. SMBus Configuration..................................................................................... 128
21.3. SMBus Operation .......................................................................................... 128
21.3.1. Transmitter Vs. Receiver....................................................................... 129
21.3.2. Arbitration.............................................................................................. 129
21.3.3. Clock Low Extension............................................................................. 129
21.3.4. SCL Low Timeout.................................................................................. 129
21.3.5. SCL High (SMBus Free) Timeout ......................................................... 130
21.4. Using the SMBus........................................................................................... 130
21.4.1. SMBus Configuration Register.............................................................. 130
21.4.2. SMB0CN Control Register .................................................................... 134
21.4.2.1. Software ACK Generation ............................................................ 134
21.4.2.2. Hardware ACK Generation ........................................................... 134
21.4.3. Hardware Slave Address Recognition .................................................. 136
21.4.4. Data Register ........................................................................................ 139
21.5. SMBus Transfer Modes................................................................................. 140
21.5.1. Write Sequence (Master) ...................................................................... 140
21.5.2. Read Sequence (Master) ...................................................................... 141
21.5.3. Write Sequence (Slave) ........................................................................ 142
21.5.4. Read Sequence (Slave) ........................................................................ 143
21.6. SMBus Status Decoding................................................................................ 143
22. UART0 ................................................................................................................... 148
22.1. Enhanced Baud Rate Generation.................................................................. 149
22.2. Operational Modes ........................................................................................ 150
22.2.1. 8-Bit UART ............................................................................................ 150
22.2.2. 9-Bit UART ............................................................................................ 151
22.3. Multiprocessor Communications ................................................................... 152
23. Enhanced Serial Peripheral Interface (SPI0) ..................................................... 156
23.1. Signal Descriptions........................................................................................ 157
23.1.1. Master Out, Slave In (MOSI)................................................................. 157
23.1.2. Master In, Slave Out (MISO)................................................................. 157
23.1.3. Serial Clock (SCK) ................................................................................ 157
23.1.4. Slave Select (NSS) ............................................................................... 157
23.2. SPI0 Master Mode Operation ........................................................................ 158
23.3. SPI0 Slave Mode Operation .......................................................................... 159
23.4. SPI0 Interrupt Sources .................................................................................. 160
23.5. Serial Clock Phase and Polarity .................................................................... 160
23.6. SPI Special Function Registers ..................................................................... 162
24. Timers ................................................................................................................... 169
24.1. Timer 0 and Timer 1 ...................................................................................... 171
Rev. 1.0
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