Currently the ROBOTIS e-Manual does not list whether the BT-430 USB Dongle is compatible with the CM-550 (or not).
But I found that the BT-430 does work quite well with the BLE Module of the CM-550 at 1 Mbps:
- First MANAGER Tool is used to set EEPROM 13 (Baud Rate UART) to 3 (i.e. 1 Mbps) - see picture below
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On the CM-550, I used a simple TASK program to acquire Yaw (which can be positive or negative). Yaw is then processed to fit its absolute value into the lowest 11 bits. Bit 12 is used as a sign bit (=0 when positive, =1 when negative) - see code section shown on the right panel. This code section is part of Function Send_Data (see Left Panel) which is used inside a FOR Loop with 400 iterations (i.e. 400 Yaw data to be sent over to the PC via the BT-430). I used a delay of 10 ms between the sending of Yaw data as RC-100 packets.
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On the PC side, I used Python and PySerial to interface with the BT-430 via COM13 set to 1 Mbps.
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Typical runtime performance is shown in picture below:
whereas ones can see an interesting pattern of FOUR Yaw data collected with Time Intervals around 1 ms (or less), followed by 1 Yaw data with a much longer and variable time intervals between 103 and 43 ms. Please note that I had imposed a 10 ms delay between consecutive data transmissions, so I cannot explain this data behavior? I was shaking the CM-550 by hand during this test, so the values for YAW are quite “reasonable”.
This means that the BT-430 allows quite fast data transfer between the PC (or SBC) and the CM-550. For example, this feature is quite handy if the user needs to pass data from a Fast Video Camera (controlled by PC/SBC) into the CM-550 or vice-versa, or from ML algorithms.
When the CM-550 came out in 2019 with the ENGINEER kits, only the BT-410 USB Dongle was available at that time - which restricted BT Comm. rate to 57.6 Kbps. But NOT ANYMORE if the BT-430 is used with the CM-550!!! 