Article Directory
Overall introduction to the course
Why do we have this course?
1. The advantages of Bluetooth 4.0 itself
Quoted from IT Encyclopedia
Bluetooth 4.0, compared with all previous products of the same type, its biggest advantage is low energy consumption, and its reduction in energy consumption can reach 90%! leap. Perhaps its low energy consumption is not particularly important to us! But for Bluetooth 4.0, lower energy consumption means that it can adapt to more fields! It allows it to complete its own work through small electronics. And because of its small size and energy-saving effect. It can reduce the size of a laptop or a mobile phone. It is because of this that it still has a place in the health market, various human body monitors, and small objects in the office. In addition, the function of Bluetooth 4.0 is still compatible with all functions of 3.0 and below!
The first time Bluetooth 4.0 was affirmed by the World Bluetooth SIG was on July 7, 2010. And launched the corresponding certification program. Since then, Bluetooth 4.0 has gone to the world and brought us convenience!
2. The importance of offering this course
3. Overall planning of the course
Bluetooth development part of the product
Bluetooth self-timer
Bluetooth LED
4. Purpose of the course
This course is designed to enable students to understand the basic principles of Bluetooth and be familiar with the basic operations of Bluetooth software.
Through this course, learn to be familiar with the principle of hardware circuit, software development process and Bluetooth protocol stack.
Learn to use 4.OBLE Bluetooth protocol stack for product development.
Understand the application of communication interface.
5. Training object
1. Developers who have learned the development experience of 51 and other single-chip microcomputers and those who have C foundation and understand the development of single-chip microcomputers. 2. Developers who
have a little foundation in hardware design and interface (SPI·uC.UART) etc.
3. Know how to use the development environment and Developers who can write functions are…
Bluetooth 4.0 BLE channel analysis and topology analysis
Bluetooth 4.OBLE channel analysis
ISM frequency band channel distribution in IEEE 802.15.4 protocol 
896MHZ channel distribution, only one channel 
Bluetooth 3.0 channel distribution 
Bluetooth 4.0 channel distribution
a total of 40 channels, 3 (0, 12, 39# channels) broadcast, 37 data channel.
Send broadcast data before connection, establish connection, all devices share these three channels, and both sides answer and then pair.
After successful pairing, use the same channel and adopt frequency hopping technology. During frequency hopping, the master device issues a frequency hopping code, and the two devices hop frequency at the same time.
Zhepu analysis
Star Topology: Playing Roles
1. The central device------host, scans the advertisement to start the connection. It acts as the host in the case of single or multi-link layer link, and supports three connections at the same time. 2.
Peripheral device------slave, advertisement The sender, which is a connectable device, acts as a slave when connected in a single link layer
broadcast structure;
1. Broadcaster—broadcasting device, not a connectable device
2. Observer——scanning advertisements, unable to initiate a connection
The establishment process of the star structure:
