Among the NuMicro® Cortex®-M4 microcontrollers (MCUs), the NUC505, NUC400, and M480 series USB devices support full speed and high speed devices. Users can select full speed or high speed devices by setting registers. In the NUC505 and NUC400 series, the register is CURSPD (USBD_OPER [2]), as shown ...

Since the LDROM function is not provided in the NUC505, SPI Flash memory must be divided into two parts: one is for storing ISP code updates, and the other is for storing application code. After power on, the NUC505 will execute ISP code in SRAM first and determine whether there is a need to update ...

As shown below, if only the internal voltage reference mode is enabled, it will be affected by the external voltage VREF pin. Therefore, floating the external voltage VREF can switch to the internal voltage.

Yes, the NUC505 Audio CODEC supports digital microphones, but only supports one set of microphone at the same time. The left and right channel data are the same. This is achieved through the digital MIC clock in PA2 (Digital MIC clock in) and PA3 (Digital MIC data out) ports to the digital audio por...

VMID is the microphone reference voltage, which must be connected to the MICN when the microphone is configured for single-ended input. As shown, the suggested components are C1=220pF, C2=1uF, R1=680ohm~2.2kohm, R2=0ohm. If it is differential input, the connection is the same as the connection on th...

In the main, add: /* Relocate vector table in SRAM for fast interrupt handling. */ { #if defined ( __CC_ARM ) extern uint32_t __Vectors[]; extern uint32_t __Vectors_Size[]; extern uint32_t Image$$ER_VECTOR2$$ZI$$Base[]; printf("Relocate vector table in SRAM (0x%08X) for fast interrupt handling.\n", ...

According to the definition of I2C BUS, when the slave is in a busy state, I2C_SCL can be pulled low, forcing transmission to be stretched. When I2C interrupt occurs, I2C_SCL will be pulled low to stop I2C communication for a while. I2C_SCL will not be pulled high until the program triggers I2C to c...

The "Use Password Offline Data" encrypts a file written to offline Flash. When a user provides Nu-Link or Nu-Link Pro for others to do programming, this can prevent the file from being read. The "Security Lock" for configuration bits protects the programmed target chips and prevents them from being ...

The VBUS capacitors need to comply with the USB-IF specification inrush current. For USB 2.0, the USB-IF defined that inrush current could not exceed 50 uC. Therefore, if the VBUS normal voltage is 5.0V (Q = CV), the VBUS capacitor shall not exceed 10 uF. Users need to design their own circuit, and ...

For the NuMicro® series that can set the Data Flash size, user can modify DFEN (Config0 [0]) to enable or disable Data Flash, and modify DFBADR (Config1) to set the base address of Data Flash and adjust the Data Flash size. After the setting, the program needs to write 1 to CHIPRST (SYS_IPRST0 [0]) ...