Unknown Delivery Status


I’ve got an end device sending messages to a coordinator in API, and sometimes, after sending the message, the end device gets a Zigbee Transmit Status frame with a 0x91 to the Delivery Status, which is not documented.

Do you have any idea what it means ?
By the way, the coordinator does not receive the said message, and the Discovery Status in the ZB Transmit Status frame is 0x00 (No discovery overhead).

Nobody can help me on this issue ?

I’m using firmware 2141 and 2941, if it can help describe the problem.

If I don’t have given enough details, please let me know.

The 0X91 is the Rx Explicit Data frame. Setting AO=1 is required for the XBee to use the explicit receive API frame (0x91) when RF data packets are received. This is required if the application needs indication of source or destination endpoint, cluster ID, and/or profile ID values used in received ZigBee data packets.
ZDO messages can only be received if AO=1. Otherwise the receive packet will have a 0x90 id. See the table on page 84 of the product manual:

Thank you for your answer, Jay.

However, the frame that I receive is not an Rx Explicit Data frame, but a ZigBee Transmit Status frame (with Frame Type 0x8B). And since AO=0 on both the coordinator and the end device, it can’t be another frame which “recovers” the ZigBee Transmit Status frame.

The 0x91 is in the Delivery Status byte (byte 8 of the ZigBee Transmit Status frame).