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Frame descriptions
User Data Relay frame - 0x2D
Digi XBee® 3 802.15.4 RF Module User Guide
204
6. Once unlocked, you may send
frames and receive AT Command
Response frames received.
a. For each frame to send, form the API Frame, and encrypt through the stream
cipher as described in the unlock procedure. See
.
b. Write the frame using one or more write operations.
c. When successful, the response arrives in one or more indications. If your stack does
not do it for you, remember to acknowledge each indication as it is received. Note
that you are expected to process these indications and the response data is not
available if you attempt to perform a read operation to the characteristic.
d. Decrypt the stream of content provided through the indications, using the stream
cipher as described in the unlock procedure. See
.
User Data Relay frame - 0x2D
Description
This frame is used to send user relay data to the Serial Port or MicroPython (internal interface). This
frame is used in conjunction with
.
For information on sending and receiving User Data Relay frames using MicroPython, see
receive User Data Relay frames
in the
MicroPython Programming Guide
.
Format
The following table provides the contents of the frame. For details on frame structure, see
Frame data fields
Offset
Description
Frame type
3
0x2D User Data Relay frame
Frame ID
4
Reference identifier
Destination interface
5
0 = Serial port (SPI, or UART when in API mode)
2 = MicroPython
Data
6
Variable length user data
Error cases
The Frame ID is used to report error conditions in a method consistent with existing transmit frames.
The error codes are mapped to statuses. The following conditions result in an error that is reported in
a
, referencing the frame ID from the 0x2D request.
n
Invalid interface (0x7C)
: The user specified a destination interface that does not exist.
n
Interface not accepting frames (0x7D)
: The destination interface is a valid interface, but is
not in a state that can accept data. For example, UART not in API mode or buffer queues are
full.