Abstract: Abstract：DSP (digital signal processor) is used more and more in the field of space. Considering the complex space environment and longterm reliable operation requirements, the capacity of onboard maintenance becomes an urgent issue which needs to be resolved for spacecraft based on DSP processor platform. Based on engineering practice, a dynamic maintenance scheme for accomplishing DSP software onboard maintenance is designed, and two different methods for generating injection instruction are proposed in this paper. By injecting the generated instructions into an appointed spare memory and enabling the hook code which is embedded in the spacecraft software in advance, the dynamic replacement function of software modules onboard operation is realized. Through the system test, the feasibility of the scheme is proved, and it has good engineering application value.  

Key words: Keywords：onboard maintenance, hook, dynamic replacement； spacecraft software