Xbee-Pro 900Hp Api Serial Exchanges; At Commands; Transmitting And Receiving Rf Data; Remote At Commands - Digi XBee-PRO XSC Manual

XBee‐PRO® 900HP/XBee‐PRO® XSC RF Modules
Checksum
To test data integrity, a checksum is calculated and verified on non-escaped data.
To calculate: Not including frame delimiters and length, add all bytes keeping only the lowest 8 bits of the
result and subtract the result 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.

XBee-PRO 900HP API Serial Exchanges

AT Commands

The following image shows the API frame exchange that takes place at the serial interface when sending an AT
command request to read or set a module parameter. The response can be disabled by setting the frame ID to
0 in the request.

Transmitting and Receiving RF Data

The following image shows the API exchanges that take place at the serial interface when sending RF data to
another device. The transmit status frame is always sent at the end of a data transmission unless the frame ID
is set to 0 in the TX request. If the packet cannot be delivered to the destination, the transmit status frame
will indicate the cause of failure. The received data frame (0x90 or 0x91) is set by the AP command.

Remote AT Commands

The following image shows the API frame exchanges that take place at the serial interface when sending a
remote AT command. A remote command response frame is not sent out the serial interface if the remote
device does not receive the remote command.
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