HAC-LBee/S manual V3.X SHENZHEN HAC TECHNOLOGY CO., LTD.
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To test data integrity, a checksum is calculated and verified.
To calculate
: Not including frame delimiters and length (1-3 bytes), add all bytes keeping only the
lowest 8 bits of the result and subtract from 0xFF.
To verify
: Add all bytes (include checksum, but not the delimiter and length). If the checksum is
correct, the sum will equal 0xFF.
5.3.2 API Types
Frame data of the UART data frame forms an API-specific structure as follows:
Figure. UART Data Frame & API
‐
Specific Structure:
The cmdID frame (API-identifier) indicates which API messages will be contained in the cmdData
frame (Identifier-specific data). Refer to the sections that follow for more information regarding the
supported API types. Note that multi-byte values are sent big endian.
AT Command
API Identifier Value: 0x08
The
“
AT Command
”
API type allows for module parameters to be queried or set. When using this
command ID, whether the new parameter values validate at once or restart next time, it is up to the
different AT Commands. Register queries (reading parameter values) are returned immediately.
Figure. AT Command Frames
(Note that frames are identical to the
“
AT Command
”
API type except for the API identifier.)
