Overall message structure with the header in the first 10 bytes and the data in the remaining, depending on the available data and SBD limitations.

Data message structure for nc = 1, cell number is sent as a UInt16, as the number of grid cells should be in the interval 256 to 65536, and where k ∈ [0, …, ld) is the data index.

当nc=1时，数据报文结构为：单元编号以无符号16位整数（UInt16）形式传输，因网格单元的数量需处于256至65536的区间内；其中k∈[0, ld)为数据索引（data index）。