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Topic: RN-41 bluetooth with an arduino (Read 2 times) previous topic - next topic

frank26080115

SJ is solder jumper

You don't need RTS or CTS

The 3.3V pin on the Uno can be used instead of a dedicated power supply circuit (I think... Only if RN-41 use less than 50 mA), but any version before Uno has a baaaad 3.3V supply from the FTDI chip and I would never use it.

You know what, I'm at work right now, but I have a way simpler way of doing level conversion than SparkFun. Level conversion can be done with a diode and a resistor, instead of the whole mosfet thing they have.

Code: [Select]


                           ^ 3.3V
                           |
                           |
                           >
                           > 10K resistor
                           >
                 diode     |
(Arduino's TX) -----|<|-----+---------- (RN-41's RX)

(Arduino's RX) ------------------------ (RN-41's TX)



use a high speed diode
Freelance engineer, consultant, contractor. Graduated from UW in 2013.

SouthernAtHeart

Thanks, to make sure I got the diode right, I drew up a quick schematic: 

Do I need to ground RTS or CTS? or just leave un connected?

frank26080115

Your diagram looks right

The diode should ideally have a low voltage drop, I forgot to mention that, get a Schottky diode

Leave RTS and CTS unconnected
Freelance engineer, consultant, contractor. Graduated from UW in 2013.

SouthernAtHeart

Thanks,
the 1N5819 is a Schottky diode, I thought?  I hope so, I've ordered some to use as motor pike shunts on my H bridge.

SouthernAtHeart

What do these numbers mean?  will the RN41 run off the Uno's 3.3 supply?

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