Just as you’ve guessed, there are only 4 broadcast channels. The reason why the N:N communication was not working is because the channel was not set properly.

The default channels for the CM-5 is 1. Normally, the channels are set so that they are unchangeable, but it can be adjusted with the R10 and R11 on the PCB.

The default channel for the CM-510 is 4, and the channel can not be changed. The default channel for the Zig2Serial is 1.

Please refer below and to the attachment on setting the channel for the Zig2Serial.

Overall, if you set the channel to 4, all can be communicated.

ROBOTIS

Here’s more information.

Instead of changing the place for the R10 and R11, please remove it.

The graph below should be easier to understand than a picture.

Normally, the CM-5’s R10 and R11 are shorted to 0 ohm. If you see the graph below it’s like being channel 1.

Once you remove R10 and R11, it will be channel 4.

 ※ Broadcasting Channel Info based on the ZIG-100’s pin status.

Here’s information on changing the  RC-100’s channel.

Setting the Broadcast Channel

If the  setting for the ZIG-100 on the RC-100Z is set to Broadcasting Mode (N:N communication  mode), you change into 4 different channels with the buttons.

Press the MODE button and desired channel number simultaneously, and the green LED will blink the number of times you have just set the channel to.

Dear Robotis,

Thank you very much for the extra information, but we would have too many CM-5s to modify if we went this route, so we decided to keep the Zig-100 "domain" (i.e. Channel 1 and CM-5s) SEPARATE from the Zig-110 "domain" (i.e. Channel 4 and CM-510/CM-700), and then use TWO USB2Dynamixel/Zig2Serial setups on the PC side (i.e. modify one special Zig2Serial to function on Channel 4 only and use 2 COM ports on the PC), and inside the code on the PC side we would just use the appropriate COM port to access either "domain" as we needed to.  Of course that is not yet allowed in the current ZigBee SDK, so Matthew had to implement a brute force approach (see Robotis's Q&A message 362 for details).  So right now, we can manage for the PC to become a base station picking up packets broadcasted from 2 independent sensor networks (one domain with CM-5s only, and the second one with a mixture of CM-510s and CM-700s).   Also this means that potentially we can use 4 ZigBee independent domains each using its own channel (but we have not tried this yet).

I cannot stress this enough: Use at your own risk!  I have never taken a C/C++ course, so better (safer) solutions are very likely.

This is the latest version of the zigbee sdk mentioned above, which allows a program to access multiple Zig2Serial dongles on multiple COM ports.  This version now uses an array of type LPHANDLE which point to the serial handles.  There are two major differences from the Robotis released drivers: 1) the added "multi_" to all function names and 2) the additional "int portHandle" parameter in all functions.  portHandle is the identifier for specifying which COM port is to be accessed; however, it is used as the index of the array so it MUST be a count (1,2,3,4,5,etc.).  portHandle is currently expected to be greater than 0, but this can easily be changed (I suspect this may have been to ensure that a COM port had been specified by the user, but I am not entirely sure anymore).

-Matt

Edited 8/27/2010: removed the sdk for revision and correction of a few typos.