AUTOSAR from introduction to mastery 100 lectures (83) - bootloader self refresh

background ：

Automotive Software Boot The main function of the program is to refresh App Program . In a specific customer project ,Boot It's also part of the customer's needs , Follow the project and have a software development plan （ Some for the sake of others Boot distinguish , Put... On the project Boot Referred to as CB, Customer Boot）. For the controller that has been offline the box cover , Whether it's in the hands of suppliers or customers , Only through CB Refresh App. if necessary CB Self refresh , You need extra methods .

standard ：

The whole vehicle factory only has the right to App Program refresh specification , No, right Boot Self refreshing norms . Because the specification is for mass production vehicles , After sales is only responsible for App Program upgrade , incorrect Boot upgrade （ Not allowed Boot upgrade ）. therefore ,Boot Self refresh only exists in the project development phase , And the supplier will provide the solution . This paper analyzes five kinds of Boot Advantages and disadvantages of self updating scheme .

Scheme 1 ：SB to update CB：

Pictured 1-a, Some software architectures have two levels Boot：SB+CB,Start Boot Check only CPU Minimum system , It has nothing to do with the peripheral circuit of the specific project , It's independent of customer needs , Maintained by the supplier , stay Pilot The project should be developed early . Because the program start sequence is SB->CB->App, In this way SB Add refresh logic to update CB. Usually it runs CB to update App Program , Under special circumstances, the program stays in after it starts SB in , to update CB.

advantage ：

1. The logical structure is simple and clear , Software division of labor is clear .

2. A refresh , Easy to operate .

shortcoming ：

1. You need a bigger one Flash Space in SB Store refresh logic in , project SOP This refresh scheme should be prohibited after , Cause extra waste .

2. The software is launched in three levels , Complicated structure , Development and maintenance costs