DB9 to BT adapter DIY? (v2.2)

[andy198712]

Hi,

I'm looking to convert to bluetooth on my MS1 2.2, a lot of people all take jumpers from inside for the module from my searching, but i have a box full of parts including some spare DB9 plugs.

now correct me if i'm wrong but the DB9 has a pin out like this

PIN1 VCC (5volts)
PIN2 TX (out)
PIN3 RX (in)
PIN5 Ground
PIN9 Ground

so can i not just wire my BT module to a spare DB9 plug in that fashion and just plug it in? that way i don't have to cut anything and can use the cable if i wish?

Cheers

Andy

PS i have the HC-06 module

[grom_e30]

the hc-06 uses ttl leval signals (5v) the serial is rs232 (+-12v) so if you connect the ttl module to the serial signals it will not be very happy

[andy198712]

the hc-06 uses ttl leval signals (5v) the serial is rs232 (+-12v) so if you connect the ttl module to the serial signals it will not be very happy

oh! i thought it was 5v, going a 3rd of the way down this pay it has the pin layout

http://www.megamanual.com/v22manual/mass.htm and says this

Pin 1 - VCC (5 volts)
Pin 2 - Tx (OUT)
Pin 3 - Rx (IN)
Pin 5 - ground
Pin 9 - ground

is that right or wrong?

[grom_e30]

5v power goes out the serial port but the communication signals rx and tx are rs232 so +12v and -12v

[andy198712]

5v power goes out the serial port but the communication signals rx and tx are rs232 so +12v and -12v

ah i see, so maybe mounting a second DB9 port next to the one i'll use for the cable and wire that for the correct 5v feed and RX and TX maybe....

i just don't want to be reliant on the BT i think? maybe i should grow a pair and just commit

That said i have some pretty good tails with my BT chip so could just wire (solder) those in to where i need to and unplug as i wish....that should work fine and no create any shorts ect right?

[grom_e30]

you could use a max232 something along these lines http://www.ebay.co.uk/itm/MAX232-RS232- ... Swwo1XdKvp to convert your rs232 signals back down to ttl and connect that to your hc-06 leaving the ecu un changed. but you may need gender/changers to plug it in to the port on the ecu

but for all the messing about you are better off buying a propper rs232 - bluetooth adapter.

[Ted75zcar]

I used an adafruit Bluefruit EZ-Link - Bluetooth Serial Link & Arduino Programmer on my MS2. It is wired into the UART on the processor side of the level translator.

I put a single pole double throw switch on the processor RX (device TX) to switch in the communication channel source. The Processor TX (Device RX) is common and un-switched.

Works great.

[Dennis_Zx7r]

That said i have some pretty good tails with my BT chip so could just wire (solder) those in to where i need to and unplug as i wish....that should work fine and no create any shorts ect right?

Including a picture: http://www.msextra.com/forums/viewtopic ... 00#p478195

[andy198712]

cheers guys.

i just multi metered my pin 1 and it gives 5v solid. so happy with that, will try just soldering my tails to a spare serial plug and just have a plug and play style one, failing that it'll be hard wired in as above (but think thats a V3 board?)

[Dennis_Zx7r]

...(but think thats a V3 board?)

It is... sorry, missed the v2.2.