双口RAM用于闪存实时数据存储研究

Dual-Port RAM's Usage in the Research of the Flash Real-Time Storage

由于NAND闪存的数据写入是以页编程为基础,因而限制了前端采样频率的提高,为此提出了采用双口RAM的双单片机系统解决方案。方案中,主单片机负责A/D转换并在片上RAM缓存数据,满200字节时打包写入双口RAM;当双口RAM缓冲区中的数据达到闪存的页容量时,由单片机读取数据,从单片机以页编程方式一次写入闪存。解决了双口RAM的端口争用问题并讨论了极限采样频率,实现了主、从单片机数据共享,缓存采集信号,即使在较高采样频率下,仍能确保及时、可靠地存储实时信号。

As the data writing operation of the NAND flash is based on the page programming, the former sampling frequency is limited on a low level. This paper offers a solution using the dual-processor system with the structure of the dual-port RAM. The master processor finishes the A/D convertion and buffers the result data on it＇s RAM until 200 Bytes before it is writen into the dual-port RAM. When the data reached the flash＇s one page, the slave processor reads the data and sends it into the flash by page programming. The research resloves the dual-port RAM＇s port competition problem and realizes the resource sharing between the master and the slave processor. Although in the higher sampling frequency, the acquired data can definitely be written into the flash in time.