How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

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grom_e30
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by grom_e30 »

you connect it inside before the signals go through the msx232 circuit, the 5v ttl signals from the processor are stepped up to rs232 signals +12/-12v by the max232. the rs232 signal would prob kill the 5v ttl bt module if you connected it directly to the serial port without using another max232 to step the signal back down.
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by racingmini_mtl »

But you can get cheap modules on ebay that already have the max232 and the DB9 connector.
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MegaMicra
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by MegaMicra »

Thanks for the info guys. So going off what you both have said, it might work if I connect one of those ready made max232 modules to my hc-05 Bluetooth module. It's only a couple of quid to try it. If not I'll just buy one of the proper Bluetooth ones.

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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by racingmini_mtl »

What I meant is that there are Bluetooth modules with everything integrated: max232, DB9 and HC-05 (or equivalent). That's much easier to deal with than separate RS232 module and Bluetooth module.

Jean

EDIT: Like this: https://www.ebay.ca/itm/DB9-RS232-RF-Wi ... 2108777586
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MegaMicra
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by MegaMicra »

Ah right I see. I could just reprogram the baud rate etc to work with my MS3X and then use the HC-05 that I've already got for the raspberry pi. Thanks for the info and link.

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jasaircraft
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by jasaircraft »

If my laptop has the rs232 port do i still need the usb-ttl converter? Or can i use a db9 connector to one of those 4pin straight connectors that go to the bluetooth adapter
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by sakurachuck »

MegaMicra wrote:Instead of putting the Bluetooth unit inside. Can it be connected to the external db9 serial port by soldering it to a connector, or will it not work that way. It's a pain removing all my ms3 from the car.

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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by misiozol »

this is what I was looking for loooong time thx ;)
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Re: How To - MS Onboard Bluetooth Cheap Ebay module (HC-05)

Post by Crazy2287 »

jasaircraft wrote:If my laptop has the rs232 port do i still need the usb-ttl converter? Or can i use a db9 connector to one of those 4pin straight connectors that go to the bluetooth adapter
No, you cannot hook the HC 05 to any standard serial port on a computer. They use 12v to communicate, HC 05 needs 3.3v (but 5v is okay)
*insert witty comment here*
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