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Help in bluetooth communication with CHR-UM6


#1

hi

i want to communicate my um6 to pc via bluetooth (EGBT-045MS) vice versa. in usb to rs232(serial com) it work perfectly i get what i expected. but when i transfer it via bluetooth, the um6 cant receive data through the bluetooth but i can transmit data from um6 to bluetooth. the bluetooth can send the packet but the receiver of um6 cant receive or cant recognize what the data has been sent. need ur help badly!
this is how the packet sent through um6.
(ignore the request_data)


unsigned char connect_data[]={'s','n','p',0,200,2,25};	
void CBluetoothDlg::Serial_USARTSend(void)
{
	int i;
	DWORD size;

	for(i=0; i<7; i++)
	{
		if(isConnected)			// for request
		{
		test.SendData(&m_hComm, &size, request_data[i]);
		Sleep(10);
		}
		else					// for connect
		{
		test.SendData(&m_hComm, &size, connect_data[i]);
		Sleep(10);
		}
	}	

}

#2

Hello.

I am sorry you are having problems using your UM6 sensor. Could you tell us more about your setup? How do you have the Bluetooth modules connected? Could you post pictures of your setup?

- Jeremy


#3

hi jeremy,

the setup on this bluetooth module(EGBT-045MS) and the um6-sensor.
the bluetooth module is in usart.
same baudrate = 38400
all connections are good (tested already)
TTL level works perfectly (3.3v)
they have common ground
supply voltage 3.7v
the program in bluetooth is tested via the PROTEUS(ISIS) simulation.


setup on the USB to rs232 cable with the serial breakout board of the um6-sensor and the um6-sensor.

same baudrate = 38400
all connections are good (tested already)
TTL level works perfectly (3.3v)
they have common ground
regulated ac/dc adaptop supply voltage 4.5v


the problem is that the um6-sensor received garbage data from the bluetooth module.
but in the serial connection using the USB to rs232 cable as shown in the image. it worked perfectly as what we expected to come out. and about the code we used the open um6-source code and for the bluetooth part we get the idea from the open um6-source code. any one have idea what’s the cause of the problem?


#4

Thank you for the photos. It is still not clear how you are sending commands via Bluetooth to your UM6. Could you post more information about the Bluetooth module that is connected to the computer? Also, could you tell me how you tested the Bluetooth module that is connected to the UM6?

  • Jeremy

P.S. Your Bluetooth module looks awesome. I would definitely like to hear more details about it (it looks like you might have salvaged an old cell phone for power).


#5

Hi Jeremy,

Sorry for the late response,after many times of testing and troubleshooting, we found that the problem is in the baudrate of the bluetooth which we though it is 38400 but it is 9600. thank you for your response.

-Rai

P.S. about the bluetooth we used EGBT 045-MS. YES, we used a cellphone battery as our supply since it has the specific volts we need and it is rechargable and it is recycle, so less cost =))…about the casing, we just salvage it.


#6

Thanks for letting us know. I am glad you were able to figure it out and get it working.

- Jeremy


#7

Good information about the Bluetooth module that is connected to the computer?


#8

Hello.

I’m not sure if I understand your question. Are you looking for more information on the Bluetooth module the original poster used?

- Jeremy