BlueSMiRF modem does not respond to '+++'

Wireless & IoT
1

Hi,

I recently bought a new BlueSMiRF Silver modem for my AVR project. I use a Bluetooth 2.0 dongle with the WIDCOMM BT stack on the PC. After a bit of experimentation I managed to set up the serial port and to get the BT modem connected to the PC (both the Widcomm software and HyperTerminal say it is connected on COM4). My problem is, it does not respond at all in HyperTerminal or RealTerm.

I have tried both 9600 8 N 1 and 115200 8 N 1 as connection settings. HyperTerminal will report a successful connection at either speed, but when I type in +++, there is no reply. Regarding the other settings (emulation: ANSIW etc.), I have followed the instructions in the “Setting Up the BlueSMiRF Bluetooth Module” document by Abe Howell.

I have tried this with the TX/RX lines connected to the AVR and without, again that made no difference, I get no reply.

Any suggestions on what I might be doing wrong or missing?

Thanks

Peter

2

Some updates to make it easier for people to help me:

  1. Base on what other people have posted, I now have CTS and RTS connected with a jumper lead and also RX and TX.

  2. I am using the Bluetooth software to establish the connection to the BlueSMiRF and it shows it is connected. The red and green LED on the BlueSMiRF are on.

  3. I am using RealTerm, based on what others have said regarding HyperTerminal.

  4. RealTerm shows it is connected to the BT modem when I start it.

  5. The moment I enter ‘+++’, the connection drops. No reply is received and both RealTerm and the Bluetooth software show the connection as disconnected now. The green LED on the BlueSMiRF goes off as well.

I hope this extra information helps someone to give me a hint on what to do!!!

Thanks

Peter

3

Since everybody is asleep in North America, I got no reply and experimented some more:

  1. With RX and TX connected at the BlueSMiRF, it will happily echo whatever you type in Hyperterminal or RealTerm. So it works as a serial port.

  2. As mentioned before, the moment I enter the default escape sequence ‘+++’, the connection drops. The green LED goes off and the Bluetooth serial connection is disconnected.

  3. I am using a BlueSMiRF Silver v2 (Philips BGB203 based) modem.

  4. With RX and TX disconnected, typing ‘+++’ does not disconnect the modem, but I still don’t get a reply. Nothing :x

I guess it makes sense that the data connection is dropped if you enter command mode with ‘+++’ and with RX and TX tied. That tells me that the escape sequence is not disabled, which is an option on this chipset. So, if command mode is enabled via ‘+++’, why don’t I get a reply in the scenario with RX and TX not tied???