XBee-Pro 900 (API): Options byte in TX Request has no apparent effect

XBEE-PRO XB09-DP Firmware version 1002 Hardware version 1B42

The options byte in a TX request packet (0x10) which should select between Unicast and Multicast (which I take to mean broadcast) has no apparent effect.

The following test was run with a pair of modems:

Sent: (Unicast) 7E 00 19 10 03 00 13 A2 00 40 53 86 E2 AB AD 00 00 48 65 6C 6C 6F 20 77 6F 72 6C 64 A8
Rcvd: 7E 00 07 8B 03 FF FE 03 00 00 71

Sent: (Multicast) 7E 00 19 10 04 00 13 A2 00 40 53 86 E2 AB AD 00 08 48 65 6C 6C 6F 20 77 6F 72 6C 64 9F
Rcvd: 7E 00 07 8B 04 FF FE 03 00 00 70

In both cases, the TX status packet reports 3 retries. I would have expected the retry count to be 0 for the Unicast TX packet and for the Multicast packet a retry count of 3 would be reasonable. It also reports 0xFFFE as the 16-bit network address, even though 0xABAD was used in the TX Request (discussed in another thread)

This is the response I got from Support when I asked for their help (they answered very quickly BTW)…

The option byte you are referring to should be left at 0x00 as this is intended to be used as a place holder for backwards compatibility with the other 802.15.4 and ZB/Znet 2.5 products.