# Modbus RTU Protocol

<table data-header-hidden><thead><tr><th width="123.05078125"></th><th></th><th></th></tr></thead><tbody><tr><td><strong>記憶體類型</strong></td><td><p><strong>唯讀型記憶體</strong></p><p> <strong>(Read-Only Memory)</strong></p></td><td><p><strong>讀寫型記憶體</strong></p><p> <strong>(Read/Write Memory)</strong></p></td></tr><tr><td>主要功能</td><td>讀取設備的即時狀態和結果</td><td>設定設備的運行參數和校正值</td></tr><tr><td>儲存內容</td><td>儲存流量狀態相關的記憶體，例如：瞬時流量、累計流量等</td><td>儲存流量設定參數相關記憶體，例如：管徑外徑、標定係數、流量截止值等</td></tr><tr><td>操作權限</td><td>只能讀取，無法寫入</td><td>可供讀取和寫入</td></tr><tr><td>功能碼</td><td>讀取指令 04</td><td><p>讀取指令 03</p><p>寫入指令 06 / 30 /31</p></td></tr></tbody></table>


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