What are the main types of dongles?
There are parallel port, serial port and USB port from the interface, the first two of which are almost out of the market.
In terms of communication protocol, there are two types: driverless and driverless. 99% of foreign products are driverless, while driverless is more popular in China. I personally think it's a 64 bit driver. If you want to install it, you need to buy Microsoft's electronic signature, while driverless ones don't need to pay for it
In terms of hardware structure, there are mainly storage type and single-chip type. At present, the so-called smart dog is popular in China, which can convert part of the code into C51 single-chip computer code and execute it in the dog (such as Jingrui IV, Jingrui e professional edition and rockey3 of Feitian Chengxin) Rockey6smart, ET199 of Jianshi Chengxin) because most of the foreign algorithms are driven, most of them complete the algorithm in the driver, and use the data of the storage unit in the dog as the seed of the algorithm