FCR Function Control Register. 0x40000800 0x00 0x400 registers FCTRL0 Register 0. 0x00 read-write USBCLKSEL USB External Core Clock Select. 16 1 sys Generated clock from system clock. 0 dig Digital clock from a GPIO. 1 I2C0DGEN0 I2C0 SDA Glitch Filter Enable. 20 1 dis Filter disabled. 0 en Filter enabled. 1 I2C0DGEN1 I2C0 SCL Glitch Filter Enable. 21 1 dis Filter disabled. 0 en Filter enabled. 1 I2C1DGEN0 I2C1 SDA Glitch Filter Enable. 22 1 dis Filter disabled. 0 en Filter enabled. 1 I2C1DGEN1 I2C1 SCL Glitch Filter Enable. 23 1 dis Filter disabled. 0 en Filter enabled. 1 FCTRL1 Register 1. 0x04 read-write AC_EN Auto-calibration Enable. 0 1 dis Disabled. 0 en Enabled. 1 AC_RUN Autocalibration Run. 1 1 not Not Running. 0 run Running. 1 LOAD Load Trim. 2 1 INV_GAIN Invert Gain. 3 1 not Not Running. 0 run Running. 1 ATOMIC Atomic mode. 4 1 not Not Running. 0 run Running. 1 MU MU value. 8 12 AC_TRIM 150MHz HFIO Auto Calibration Trim 23 9 FCTRL3 Register 3. 0x0C read-write DONECNT Auto-calibration Done Counter Setting. 0 8 URVBOOTADDR Register 4. 0x10 read-write BOOTADDR RISCV Boot Address. 0 32 URVCTRL Register 5. 0x14 read-write SLEEP_REQ Sleep Request to RISCV. 0 1 SLEEP_ACK Acknowledgement of Sleep Request for RISCV. 1 1 GP General Purpose Register. 0x1C read-write GP General Purpose. 0 32 TRIMCTRL MSR ADC Trim Register. 0x20 read-write MSR_R1 MSR R1 0 2 0K 0kOhm 0 1P2K 1.2kOhm 1 2P4K 2.4kOhm 2 4P8K 4.8kOhm 3 MSR_R2 MSR R2 2 3 OPEN Open drain. 0 3K 3kOhm 4 6K 6kOhm 5 12K 12kOhm 6 24K 24kOhm 7 ERFOKS ERFO Kick Start Register. 0x24 read-write CTRL Kick Start Control. 0 16