GE DS200SDCCG1AHD自动化控制模块
数据包格式完整的请求/响应序列由以下字节组成（作为单独的数据帧传输）：主请求传输：从属地址：1字节功能代码：1字节数据：取决于功能代码的可变字节数CRC：2字节从属响应传输：从属地址：1字节函数代码：1个字节数据：根据功能的可变字节代码CRC：2字节•从属地址：每次传输的第一个字节。它表示被分配用于接收主设备发送的消息的从属设备的用户分配地址。每个从属设备必须分配一个唯一的地址，以便只有它响应以其地址开头的传输。
Data Packet Format A complete request/response sequence consists of the following bytes (transmitted as separate data frames): Master Request Transmission: SLAVE ADDRESS: 1 byte FUNCTION CODE: 1 byte DATA: variable number of bytes depending on FUNCTION CODE CRC: 2 bytes Slave Response Transmission: SLAVE ADDRESS: 1 byte FUNCTION CODE: 1 byte DATA: variable number of bytes depending on FUNCTION CODE CRC: 2 bytes • SLAVE ADDRESS: The first byte of every transmission. It represents the user-assigned address of the slave device assigned to receive the message sent by the master. Each slave device must be assigned a unique address so only it responds to a transmission that starts with its address.
