mBlock does not recognise serial ports beyond com20

#1

If have connected my Orion board to my PC and it has already allocated many coms ports to other devices. My Windows 10 PC allocated com47 to Orion. mBlock does not show this port and I can not now connect. For the last 12 months I have had no problems getting a connection and it is usually below com20. Is there a bug with mBlock and how can I get a connection to Orion on com47? I also noticed the same problem with MusicBot on my PC. I have no problems accessing the Orion board from the Arduino IDE and other programs such as node-red.

I am using a Windows 10 PC and have used mBlock on numerous occasions before. Had the same problem on the latest version of mBlock (v3.4.9) and the previous version (v3.4.6) I had installed.

#2

Hi philip,

Normally, the USB connection between Computer and the Makeblock board won’t be matched to the COM port number bigger than 20.
If it is, there should be many com ports for the history paired Bluetooth devices. Please uninstall those paired Bluetooth devices on the computer will resolve this issue.

#3

Thanks for the prompt reply. Could this be fixed in future versions as it is not an issue in other Arduino software such as the IDE. As suggested I uninstalled the other bluetooth devices but I am always experimenting with many coms devices and this should not be necessary.

#4

Hi dsrc12

Thanks for sharing your opinion.
The mBlock software is keeping improving. After consulted our engineers, we know that there is plan to add serial port optimization for mBlock software in the future too. Hopefully this problem should be solved in the future. Please kindly wait.

#5

Hi. Windows keeps a database of serial ports inside of a registry key based on a bitmap. The bitmap states with a 0 (zero) that the port is NOT present. With a 1 (one), the port is present.

So for example, if the bit map value is “B” (hex) = bitmap is “1011” = meaning that:
COM1 ; is present
COM2 ; is present
COM3 ; NOT present
COM4 ; is present

Have said the above, you can manually enter the regedt tool and clean up the phantom serial port database. The registry key is called COM NAME Arbiter.

There are many articles on the internet that discuss this topic but here are a few:

ftp://ftp1.digi.com/support/images/phantom_port_removal_on_windows_.htm

Once you do this, power cycle Windows and then dock your USB com port and you should see the COM port being enumerated as the next free COM port mailbox. Good luck!

PS: We are a manufacturer of add-on serial ports so hear about this issue often :slight_smile:

#6