熊啟龍

　　(水利部淮河水利委員會水文局(信息中心)，安徽 蚌埠 233001)

　　摘 要：為在水文自動測報系統遙測站的遙測終端機中基于NOR Flash存儲器可靠地存放系統運行參數，分析遙測終端機中常用固態存儲器的讀寫特點和KV鍵值數據庫的實現方式，設計一種基于W25Q256存儲器實現KV鍵值數據庫的解決方案。方案充分應用NOR Flash存儲器的讀寫特點，針對同一個地址重復寫入的最小編程顆粒度為1 bit，結合KV鍵值實現一個鍵值對狀態的順序變化，進而通過在存儲器的一段空間內順序增加地址存放KV鍵值對，實現KV鍵值對的新增、修改、刪除和檢索操作，達到磨損均衡和異常掉電恢復效果。在嵌入式系統中，相較于常用的采用固定地址保存運行參數的方案，該研究方案能有效延長NOR Flash存儲器的使用壽命，提高系統的穩定可靠性。

　　關鍵詞： NOR Flash;KV鍵值對;KV數據庫;W25Q256存儲器;遙測終端機;運行參數;磨損均衡;掉電恢復

　　Application research of KV database based on NOR Flash

　　XIONG Qilong

　　(Hydrological Bureau of the Huaihe River Water Conservancy Commission (Information Center，Ministry of Water Resources，Bengbu 233001，China)

　　Abstract: In order to reliably store the system operating parameters based on NOR Flash memory in remote telemetry unit (RTU) of telemetry station of hydrological automatic measurement and reporting system and analyze the implementation mode of common Key-value database and the reading and writing characteristics of common solid-state memory in telemetry terminal, the solution to realize KV database based on W25Q256 memorizer is designed. Aiming at the minimum programming granularity of repeated writing at the same address is 1bit, the scheme makes full use of the reading and writing characteristics of NOR Flash memory, realizes sequential change of KV pair states by combining with the kV key value, and store the KV pair by sequentially adding an address in a section of memory space to realize the sequential cyclic addition, modification, deletion and retrieval of KV pairs. In embedded system, this research scheme can effectively prolong the service life of NOR flash memory and improve the stability and reliability of the system, compared with the common scheme of using fixed address to save operating parameters.

　　Key words：NOR Flash;key-value pairs;key-value database;W25Q256 memorizer;remote telemetry unit;operating parameters;wear levelling;power loss protection