基于RS485的多DSP系统在线升级程序方法研究

On-line updating program of Multi-DSPs based on RS485

为解决密封性要求高、拆卸难度大、多DSP模块的大型复杂系统使用半双工RS485在线升级任意DSP程序的问题,设计了一种基于RS485总线在线升级程序的方法。此方法需要二次引导程序、应用程序和上位机程序的相互配合。首先,上位机程序和应用程序通过RS485通信确定待升级程序的DSP模块。然后,应用程序通过电可擦出可编程只读存储器将消息传递给二次引导程序。最后,上位机软件将待升级软件转换成的二进制数据通过RS485发送给二次引导程序,由二次引导程序接收并固化到片载闪存,完成程序在线升级。实验表明,此方法操作方便且能保证仪器的密封性,效率得到十倍以上的提升,具有非常高的工程应用价值。

Some hermetically sealed and non-easy-disassembled embedded system has many modules which use DSPs as its controllers.In order to online update any DSP's software in the system,this paper designs a method using RS485.This method requires joint efforts among secondary bootloader, embedded application and computer application.Firstly,the communication by RS485 between embedded application and computer application decides which DSP's software to be updated.Next, embedded application sends the decision to secondary bootloader by accessing EEPROM.Finally, computer application sends binary data converted by code to DSP,and the DSP receives the data and then store it into FLASH,a built- in memory in DSP.Experiments show that this method is easy to manipulate and highly efficient,and can maintain leakproofness effectively.The efficiency increases by more than ten times.Therefore,this method is of great value in practice.