Cell phone serial port to Bluetooth module


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Hello All.

I hope I may find some proper direction from someone here to assit me in making this work.

I am trying to get a Bluetooth link to work from my non Bluetooth cell phone. Its a old phone but I require this exact phone for my needs.

I am trying to create a Bluetooth Link to my laptop and/or tablet at 38400 baud to the phone.

Using the data cable to serial cable I purchased it works just fine with my USB -> serial adapter.

The data cable after some disassembly is using the following lines.

on the db9 and what I believe it is


2 RX

3 TX


5 Signal Ground

6 N/C



9 Ring

I am using a RS232 to TTL converter based on the SP2323EEN Chip

I have been waiting on some Voltage regulators and have been running both units off of 2 AA batteries to supply it the above +3 to make them work for the moment.

I can hook this up to a PC and run Hyperterm.. and sync the BT on another PC and load Hyperterm and am able to send/receive text at 38400 baud just fine.

So I know the issue lies in the RTS/CTS and possible DCD and DTR.

I tried to loop them like you would with a null modem and no go.

I assume on the modem/Phone side to enable DTR and DCD it requires voltage to make them HIGH? and possible the same for CTS/RTS. If so, how could i go abouts getting those working. Is there more than just voltage? I know taking my meter to the device when connected via the standard serial connection between PC and phone im readying around 7 volts on those lines

If anyone can get me a bit closer on this project I would be greatly appreciated.

Attached are pics of the 2 hardware devices I am working with.





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