Identifying duty exemptions via HS code

List of contents of this article:

• 1,Identifying duty exemptions via HS code STM32F103C8T6 port?
• 2, In the STM32F103 minimum system, how big is the capacitance connected next to the 8MHz crystal oscillator?
• 3, What is the difference between the minimum system circuit of STM32F103VET6 and STC15W4K48S4 single-chip microcomputer?
• 4, What do you think of the pin of STM32 minimum system?

STM32F103C8T6 port?

Channel 0 corresponds to PA0, Channel 1 corresponds to PA1, Channel 2 corresponds to PA2, Channel 3 corresponds to PA3, and so on. The default options include PA0's foot and ADC123_IN0, which means that when PA0 collects pins from ADC, the channel0 of ADC1, 2 and 3 modules can be used.

STM32F103C8T6 is a single-chip microcomputer chip designed by STMicroelectronics. It adopts the Cortex-M3 kernel, the main frequency is 72MHz, and the memory includes 64KB flash memory, 20KBSRAM and 2KBEEPROM.

WeThe commonly used model is STM32F103C8T6, and the following is based on STM32F103C8T6. Secondly, the STM32F103 series chip defines only two pins for USB function, which are USBDM and USBDP. In the form of 48-pin packaging, USBDM is in pin 32, corresponding to PA11; USBDP is in pin 33, corresponding to PA12.

STM32F103C8T6 is a 32-bit single-chip microcomputer based on the ARM Cortex-M kernel, which can make some simple products, such as bracelets, watches, temperature and humidity detectors, etc. Serial interface, also known as serial communication interface or serial communication interface (usually refers to COM interface), is an extended interface that adopts serial communication.

In the STM32F103 minimum system, how big is the capacitance connected next to the 8MHz crystal oscillator?

The linear parasitic capacitor is generally 3~5pF. According to the relevant information of the query, it can be found from the ST manual that the crystal input capacitance of STM32F103 is 5pF, while the parasitic capacitance of PCB wiring can be estimated at 3pF to 5pF.

The crystal vibration capacitor is located on the two feet of the crystal vibration. In the STM32F103RCT6 chip, the external crystal oscillator needs to be connected to the pin of the crystal with two capacitors. These capacitors are called load capacitors, which help stabilize and adjust the frequency of crystals.

A resistor of about 10M is connected in parallel between the two pins of the crystal vibration.

If the capacitor is 10uF, the resistance is about 20K. The power-on reset is generally the RC charging and discharging circuit.

The capacitor in the crystal oscillation circuit of a single-chip microcomputer is called the load capacitance, which can also be said to be the starting capacitor. Generally, there are two small capacitors in the crystal oscillation circuit. The crystal vibration work of the single-chip microcomputer is in a parallel resonance state, which can also be understood as part of the resonance capacitor.

What is the difference between the minimum system circuit of STM32F103VET6 and STC15W4K48S4 single-chip microcomputer?

1. The difference between the two is particularly big. I suggest using a small difference.

2. The former is a 32-bit single-chip microcomputer, and the latter is an 8-bit single-chip microcomputer. It is not the same grade, the internal resources are very different, and the comparability is not strong. For example, RAM, the former is 64KB, and the latter is only 4KB. FLASHROM, the former is 512KB, and the latter is only 48KB. The difference is more than 10 times.

3. The chip of the single-chip microcomputer is different. The peripheral circuits are different. The others are the same.

What do you think of the pin of STM32 minimum system?

1. The range of the input level of the STM32 pin is ALVC, the input is less than 0, the input is greater than 2V is counted as a high level, and 8V in LV and ALVT is counted as a low level.

2. We can see the metal pins arranged around the single-chip microcomputer. These pins are called pins. The following figure shows the specific functions of different pins of the ATMEGA328P-AU single-chip microcomputer. The pins can be roughly divided into 4 categories: the positive pole of the power supply (VCC) marked in red and the negative pole of the power supply marked in black. Pole (GND), these pins are used to power single-chip microcomputers.

3. The pin functions of stm32 are as follows: GPIO pin, ADC input pin. GPIO pin: The GPIO pin in STM32 is mainly used for input and output digital signals, and the pin status can be controlled by programming. ADC input pin: used to connect analog input signals, such as temperature, light intenss, etc., and convert them into digital signals.