Interpreting message type 0xA1 when numAddr=0 or hop=0x0000

I am processing API message 0xA1 (route record indicator) and need help interpreting two different things:

  1. What does it mean when the numAddresses is 0?

  2. What does it mean when numAddresses is 1 but the hop is 0x0000 ?

Based on the proximity of the devices, the real situation should be “direct” for both. The odd thing is that I see this coming from the same coordinator on a periodic basis. It’s just that sometimes the message changes from 0 addresses to 1 (with 0x0000 as the only hop).


Maybe you should provide the API frame you are getting and indicated which XBee product and firmware you are working with?

I tried to ask pretty specific questions so that I didn’t have to confuse things with pages of hex messages. Really what I’m asking for is documentation clarification on a couple of the message formats.

My questions were:

  1. If you receive an 0xA1 message (route discovery) with a no addresses, examples notwithstanding, does that imply “direct to coordinator?”

  2. Is 0x0000 ALWAYS the coordinator per ZB spec?

The manual 90000976_V page 145 makes reference to Table 1-03 in Chapter 1, but I don’t know what that references - there is no Table 1-03 that I can find (at least they aren’t labeled). I’m not sure if they mean a different manual.

Don’t get me wrong here, I’m full of praise for this documentation - there’s just a few things here and there that are a bit open-ended… and examples of some of the AT frames as they come back in API format would be extraordinarily helpful. Even the X-CTU tool tends to take things like what I pasted above and dump the meaty part out as a string of hex digits that I have to interpret myself.

I’ll ask a more specific follow-up question on ND packets shortly.