A chip access control method is proposed in this paper to solve the file access control problem of multi-applications chip. Firstly

a security state machine is designed

which subdivides the access right into 32 levels. Driven by user instructions

the security state machine undergoes security state transition. Only when the security state meets the preset file access conditions

file access is allowed. At the same time

in order to isolate the access right of different applications

the environment state machine and the application state machine are defined. The environment state machine controls the access authority of the chip as a whole

the application state machine controls the access authority of a single application

and through the combination of two state machines

the fine management of chip file access control is realized.