The Command Interface - We PROTEUS-III User Manual

WIRELESS CONNECTIVITY & SENSORS
User manual Proteus-III

7. The command interface

The module acts as a slave and can be fully controlled by an external host. The configuration
as well as the operation of the module can be managed by predefined commands that are sent
as telegrams over the UART interface of the module.
The commands of the command interface can be divided into 3 groups:
• Requests: The host requests the module to trigger any action, e.g. in case of the request
CMD_RESET_REQ the host asks the module to perform a reset.
• Confirmations: On each request, the module answers with a confirmation message to
give a feedback on the requested operation status. In case of a CMD_RESET_REQ , the
module answers with a CMD_RESET_CNF to tell the host whether the reset will be performed
or not.
• Indications and Responses: The module indicates spontaneously when a special event
has occurred. The CMD_CONNECT_IND indicates for example that a connection has been
established.
Start signal
0x02
Start signal: 0x02 (1 Byte)
Command: One of the predefined commands (1 Byte).
Length: Specifies the length of the payload that follows. Length is a 16 Bit field with LSB first.
Payload: Variable number of data or parameters (defined by the length field).
Checksum: Byte wise XOR combination of all preceding Bytes including the start signal, i.e.
0x02 ˆ Command ˆ Length ˆ Payload = CS
Host integration example codes for checksum calculation and command frame
structure can be found in annex A and B , as well as in the Wireless Connectivity
SDK .
If the transmission of the UART command has not finished within the packet
transmission duration (depending on the currently selected UART Baud rate +
5ms after having received the start signal), the module discards the received
Bytes and waits for a new command. This means that the delay between 2
successive Bytes in a frame must be kept as low as possible.
Order code 2611011024000
Version 1.8 , July 2022
Command Length
1 Byte 2 Byte, LSB first
Payload CS
Length Bytes 1 Byte
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