C8051F02X Datasheet, PDF (5/272 Pages) Silicon Laboratories – 8K ISP FLASH MCU Family

C8051F020/1/2/3
16.1. Accessing XRAM..........................................................................................................145
16.1.1. 16-Bit MOVX Example.......................................................................................145
16.1.2. 8-Bit MOVX Example.........................................................................................145
16.2. Configuring the External Memory Interface .................................................................146
16.3. Port Selection and Configuration ..................................................................................146
16.4. Multiplexed and Non-multiplexed Selection.................................................................148
16.4.1. Multiplexed Configuration ..................................................................................148
16.4.2. Non-multiplexed Configuration...........................................................................149
16.5. Memory Mode Selection ...............................................................................................150
16.5.1. Internal XRAM Only ...........................................................................................150
16.5.2. Split Mode without Bank Select ..........................................................................150
16.5.3. Split Mode with Bank Select ...............................................................................151
16.5.4. External Only .......................................................................................................151
16.6. Timing .......................................................................................................................151
16.6.1. Non-multiplexed Mode........................................................................................153
16.6.1.1. 16-bit MOVX: EMI0CF[4:2] = ‘101’, ‘110’, or ‘111’................................153
16.6.1.2. 8-bit MOVX without Bank Select: EMI0CF[4:2] = ‘101’ or ‘111’............154
16.6.1.3. 8-bit MOVX with Bank Select: EMI0CF[4:2] = ‘110’. ..............................155
16.6.2. Multiplexed Mode................................................................................................156
16.6.2.1. 16-bit MOVX: EMI0CF[4:2] = ‘001’, ‘010’, or ‘011’................................156
16.6.2.2. 8-bit MOVX without Bank Select: EMI0CF[4:2] = ‘001’ or ‘011’............157
16.6.2.3. 8-bit MOVX with Bank Select: EMI0CF[4:2] = ‘010’. ..............................158
17. PORT INPUT/OUTPUT .....................................................................................................161
17.1. Ports 0 through 3 and the Priority Crossbar Decoder....................................................163
17.1.1. Crossbar Pin Assignment and Allocation ............................................................163
17.1.2. Configuring the Output Modes of the Port Pins ..................................................164
17.1.3. Configuring Port Pins as Digital Inputs ...............................................................165
17.1.4. External Interrupts (IE6 and IE7) ........................................................................165
17.1.5. Weak Pull-ups......................................................................................................165
17.1.6. Configuring Port 1 Pins as Analog Inputs (AIN1.[7:0])......................................165
17.1.7. External Memory Interface Pin Assignments ......................................................166
17.1.8. Crossbar Pin Assignment Example......................................................................168
17.2. Ports 4 through 7 (C8051F020/2 only)..........................................................................177
17.2.1. Configuring Ports which are not Pinned Out.......................................................177
17.2.2. Configuring the Output Modes of the Port Pins ..................................................177
17.2.3. Configuring Port Pins as Digital Inputs ...............................................................178
17.2.4. Weak Pull-ups......................................................................................................178
17.2.5. External Memory Interface ..................................................................................178
18. SYSTEM MANAGEMENT BUS / I2C BUS (SMBUS0) .................................................183
18.1. Supporting Documents ..................................................................................................184
18.2. SMBus Protocol.............................................................................................................185
18.2.1. Arbitration............................................................................................................185
18.2.2. Clock Low Extension...........................................................................................185
18.2.3. SCL Low Timeout ...............................................................................................186
18.2.4. SCL High (SMBus Free) Timeout.......................................................................186
Rev. 1.4
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