Com Port Limit

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hassenplug
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Com Port Limit

Post by hassenplug »

OK, this may sound extreme, but it appears as though Bricxcc has a limit on the com port number it can connect to. I just connected an NXT to my laptop (first time this NXT has been connected) and it was assigned com port 287. Unfortunately, Bricxcc doesn't seem to recognize the NXT as being connected. I tried for quite a while, with no luck.

I switched to NXT-G, and was able to connect and change the name of the NXT with no problem.

Looks like I'll be using NXT-G for this project.

Steve
---> Link to lots of MINDSTORMS stuff under my picture --->
mightor
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Re: Com Port Limit

Post by mightor »

You can probably prune the list of com ports quite easily. Windows assigns a com port to each device you've ever connected to it with a different "ID". Here's how to do it:
  • Open a command prompt as Administrator
  • Type "set devmgr_show_nonpresent_devices=1", followed by Enter
  • Type "start devmgmt.msc"
  • In the "View" menu, click "Show hidden devices"
  • Uncollapse the "Lego Devices" branch
  • Remove the old entries (with uninstall - do not click "delete driver")
  • Do the same for any stale entries in the "Ports (COM & LPT)" section
  • You may need a reboot, don't know.
Lego devices with no NXT connected:

Image

Lego devices with 1 NXT connected:

Image

You can easily see which one is currently connected. I just tested it on my own laptop with the one entry that becomes active when I connect one of my NXT. I disconnected the NXT, removed the entry, reconnected my NXT and the driver was reinstalled. Easy peasy.

Bluetooth com port entries:

Image

- Xander
| My Blog: I'd Rather Be Building Robots (http://botbench.com)
| RobotC 3rd Party Driver Suite: (http://rdpartyrobotcdr.sourceforge.net)
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| and then two they hav erpoblesms. (@nedbat)
mattallen37
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Re: Com Port Limit

Post by mattallen37 »

Xander, thanks for that information. I was able to open up a few COM ports myself (although it wasn't close to 255, or whatever). For the future, is there a faster way to do it (instead of typing into the command prompt)? Thanks again.
Matt
http://mattallen37.wordpress.com/

I'm all for gun control... that's why I use both hands when shooting ;)
mightor
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Re: Com Port Limit

Post by mightor »

No, there's no real shortcut unless you make a script :)

- Xander
| My Blog: I'd Rather Be Building Robots (http://botbench.com)
| RobotC 3rd Party Driver Suite: (http://rdpartyrobotcdr.sourceforge.net)
| Some people, when confronted with a problem, think, "I know, I'll use threads,"
| and then two they hav erpoblesms. (@nedbat)
afanofosc
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Re: Com Port Limit

Post by afanofosc »

BricxCC does not use the COM port numbers to connect to the NXT. These are for RCX serial port IR tower connections only.

To connect to an NXT via Bluetooth you should use a bluetooth brick resource string or a short alias for a full bluetooth brick resource string. If you can connect via the LEGO MINDSTORMS NXT software then you should also be able to connect via BricxCC since they both use the Fantom drivers to make the connection.

First, make sure you have the latest BricxCC release (3.3.8.9). There were some changes to improve bluetooth connectivity when downloading programs to the NXT using the internal compiler. Read the BricxCC and the Bluetooth Blues blog post on the Mindboards blog:

http://sourceforge.net/apps/wordpress/m ... oth-blues/

Check your nxt.dat file at %appdata%\JoCar Consulting\BricxCC\3.3\ to see if BricxCC automatically added a bluetooth brick resource string to the file. The string looks like this:

BTH::BNXT=BTH::BNXT::00:16:53:0A:75:7B::1

If something like that is in your nxt.dat file then you would see both BTH::BNXT and BTH::BNXT::00:16:53:0A:75:7B::1 listed in the Ports drop down list. Either one of these should work fine. You can also type in a brick resource string into the ports edit field if your NXT's brick resource string is not listed. I would put it into the nxt.dat file manually rather than repeatedly type it in manually, though. As mentioned in the blog post, your bluetooth brick resource string will use a different NXT name than mine (BNXT) does and it will use your NXT's unique ID rather than mine (00:16:53:0A:75:7B).

Please let me know if this does not help you connect to your NXT via bluetooth.

John Hansen
Multi-platform LEGO MINDSTORMS programming
http://bricxcc.sourceforge.net/
hassenplug
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Re: Com Port Limit

Post by hassenplug »

And so this gets curiouser and curiouser...

Maybe I hadn't fully thought this through, however Bricxcc was not able to connect the that NXT using any method. I connected the brick via USB, ran Bricxcc, Selected "Find Brick">Automatic, and instead of instantly finding the brick, it went into the bluetooth search.

NXT-G has no problem finding the brick; Bricxcc can not find the brick.

Steve
---> Link to lots of MINDSTORMS stuff under my picture --->
afanofosc
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Re: Com Port Limit

Post by afanofosc »

It is best to not use automatic when connecting to an NXT using BricxCC. Either use "usb" if you usually connect via USB or an alias from the ports list that is for your NXT (either a USB alias or a bluetooth alias, depending on how you want to connect to the NXT). Does BricxCC connect to your NXT when you use "usb" as the port name? Can you try a full USB brick resource string or a Bluetooth alias? Did you try that option? I can't tell from your response if you read the article and tried what it suggested or not.

John Hansen
Multi-platform LEGO MINDSTORMS programming
http://bricxcc.sourceforge.net/
hassenplug
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Re: Com Port Limit

Post by hassenplug »

I have not tried connecting in other ways (with the full string) yet. I just wanted to add that I was connecting via usb. I will try again next week. Thanks for the info.

Steve
---> Link to lots of MINDSTORMS stuff under my picture --->
afanofosc
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Re: Com Port Limit

Post by afanofosc »

Steve,

Were you able to connect to this NXT via USB or Bluetooth using the information I provided? If not, I would like to work with you to figure out what I am doing differently than the LEGO MINDSTORMS NXT software.

John Hansen
Multi-platform LEGO MINDSTORMS programming
http://bricxcc.sourceforge.net/
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