LMX9838 pairing connection problem

I also try to use hyper terminal and SB smart software.The problem is same "unable to  open COM8 ".Could you help to tell me what problem is.Thank you.

Hi John,

Just trying to understand the setup here. Do you currently have a computer connected to a Bluetooth device, which is wireless linked to the LMX9838? Or do you have the LMX9838 connected on the computer, and trying to connect to another Bluetooth device?

Also, are you using any sort of USB-Serial adapter? From our experiences of using different adapters, they may take more than 1 COM ports and you would have to try the different ports. FYI the port assignments can be found in Device Manager.

Hi Ryan,

I've a bluetooth connection from computer linked to the LMX9838 that worked in the Master mode.The connection is good. I also can saw that the windows7 allocate COM8 to this connection.But I can't open this COM port.

Also,I don't use any USB-Serial adapter.Just using a COM port on the mainboard

Hi John,

Just to clarify, are you using the LMX9838 dongle? Or are you implementing the LMX9838 chip yourself and writing your own software?

When you connect the LMX9838 to the laptop and run it with SBsmart, it also shows the COM port problems?

Just to let you know, you can have the SBsmart and the terminal open at the same time. The SBsmart occupies the COM port.

Hi, Ryan,

I didn't use LMX9838 dongle. I used microcontroller to control LMX9838 chip. The problem is also occurred on the SBsmart when I use laptop to connect this LMX9838  chip which worked in the master mode. I didn't use SBsmart and  terminal open COM port at the same time.Just using one software. But it also told me that the COM can't open. thank you.

Hi John,

Looking into the "Apro Exception" error, there are a couple of things you can try:

- check if any other device is connected to the same COM port

- disassociate Bluetooth or however Windows is associating the device in control panel

- disable the COM port and enable it again

Let me know if any of these help. I'll keep looking into it :) 

Hi,Ryan,

The problem was still exist. I guess the problem is the different mode in the windows 7 driver for bluetooth. When we build a bluetooth connection among LMX9838,we need to send SPP establishment command from the master 9838 to slave 9838. And the master need to allocate different local COM port in the master 9838 to the slave 9838. Every local COM port and slave 9838 is  one-to-one correspondence.So we can built multipoint connection among 9838. But in the windows 7, when windows 7 found the master 9838, it just paired it and allocate COM port in the windows 7 to the master 9838. My question is which local COM port in the master 9838 correspondence this connection. Do I need send a SPP establishment command to the windows 7.May be it's a problem.Thank you

Hi John,

Can you describe the exact operations that are performed? If you can provide the commands log from all the LMX modules in the communication system it'd be great.

Two possible reasons which are guessing at the moment:

1. Please note that PC BT stack does not use the same COM port for master and slave operations. In the other words if COM8 is used when connection is initiated by PC (being a master) then different COM number is used when the connection is initiated by the external device.

2. The module that is called a Master LMX must have enough SPP ports enabled because it uses 3 for communication with slaves and needs another one to talk to PC.

Hi John,

Any follow-ups on this?

Hi John,

Do you have any updates on this?

Ryan

Hi Guys,

I want SBsmart & Simply blue commander software. Is any body has both these software. Please mail me on my mail id i.e manojbansal6@gmail.com.

Thanks in advance.

Regards

Manoj 

Hi Manoj,

You can download the package with the software from here: http://www.ti.com/tool/lmx9838-sw

Ryan Lin