I now understand what a bus is, that is, a lot of devices are connected to one line. For example, IIC SPI is like this. The device must be selected before communication.
So don't think it is very abstract when you see the concept of the bus in the future. Like the bus in the STM32 architecture, there are high-speed buses and low-speed buses. The high-speed and low-speed should refer to the communication protocol they follow.
After learning those serial communication protocols, I understand a lot of things! ! ! ! ! !
There can be multiple masters and multiple slaves. When multiple masters initiate a request, the bus will make a ruling.
This is consistent with my understanding of the bus. From the physical level, the bus is just a few lines, and the key is those protocols.
Now look at what is said here, the devices connected to the bus are divided into master and slave, you will understand what it means, you didn't understand before, right? 4 drive units and 4 passive units.
The bus bridge should be a protocol conversion. I searched it and it was true. Now I look at STM32 and look at DE1-SOC more clearly! ! ! ! ! ! ! ! !
I think the communication between FPGA and ARM is nothing. It can also rely on some kind of communication protocol. FPGA can also write some kind of serial port. So I think the DE1-SOC board is nothing. The valuable thing about FPGA is that it can directly program and output the waveform we want, right, I want to go back to learn FPGA now. Really. It's really interesting to get this all done. This is called professionalism. Have a deeper knowledge and understanding of the entire embedded system. Now ask me to look at an embedded development board, I can see a deeper level.
Looking back at the DE1-SOC board now, you can use FPGA alone as an FPGA development board, or you can use ARM alone as an ARM linux development board, or you can use it in combination. It is really a good board. , It's a pity that you didn't understand so deeply.
I now look at the DE1-SOC notes that someone gave me before, and now I can understand most of them. Really, most of it at least knows what's going on, but you didn't understand it before and didn't know what he wrote. This may be a change after learning Huaqing's serial protocol class.
