frank26080115:
SJ is solder jumperYou 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.
^ 3.3V
|
|
>
> 10K resistor
>
diode |
(Arduino's TX) -----|<|-----+---------- (RN-41's RX)
(Arduino's RX) ------------------------ (RN-41's TX)
use a high speed diode
Can I do a similar thing to use the 5V FTDI cable from sparkfun to upload sketch to a 3.3Volt pro mini?
Here's a schematic I drew up:
5V-FTDI for 3.3mini.sch (11.8 KB)