Checksum; Xbee Api Uart Exchanges; At Commands; Transmitting And Receiving Rf Data - Digi XBee User Manual

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XBee/XBee-PRO DigiMesh 2.4 User Manual
API Frame Names
Modem Status
Transmit Status
Receive Packet (AO=0)
Explicit Rx Indicator (AO=1)
Node Identification Indicator (AO=0)
Remote Command Response

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 API UART Exchanges

AT Commands

The following image shows the API frame exchange that takes place at the UART 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 UART 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 transmit request. If the packet cannot be
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API ID
0x8A
0x8B
0x90
0x91
0x95
0x97
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