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By hahanoob
#114892
I have an Arduino Uno and I just got a WiFly GSX Breakout. I'm new to this so I'd like to verify I'm not going to destroy anything while trying to connect them.

Looking at the reference guide (http://www.sparkfun.com/datasheets/Wire ... SX-um2.pdf) it says I should connect 3.3v to both VDD-BATT and V3.3IN. So I think I'll run 3.3V from the Arduino to VDD-IN in on the breakout and then use any digital pin on the arduino (set to output, and high) to connect to VBATT. Good so far? No fire?

It looks like the only other things I need to do is then to connect Gnd to ground, and RX, TX to RX, TX on the Arduino. And maybe hook up some LEDs to SPIO 4-6.

Thanks!

[EDIT] Okay so good thing I decided to double check. I though I had read the voltage from the pins was 3.3V but looks now like it's 5V. So I guess I need to use a voltage regulator?
#114963
hahanoob wrote:I have an Arduino Uno and I just got a WiFly GSX Breakout. I'm new to this so I'd like to verify I'm not going to destroy anything while trying to connect them.
  • "Ultra-low power (4uA sleep, 40mA Rx, 210mA max Tx)" (WiFly) vs "A 3.3 volt supply generated by the on-board regulator. Maximum current draw is 50 mA." (Uno)
  • "PIO’s are not 5.0 VDC tolerant. If using a 5.0 VDC circuit, input, PIO and UART input pins require a resistor divider. A suggestion is to use a 10K resistor in series with 20k resistor to ground." (WiFly)
So I guess I need to use a voltage regulator?
You'll need to wire up a 3.3V voltage regulator to supply enough current. Then you'll need to use some form of level conversion for the communication lines.

--Philip;
#115027
Okay, thanks! I'm going to run through my plan one more time to be sure I have everything. I'm just going to hook up 3.3v on the Arduino directly to VDD-BAT and VDD-IN like before. GND right to GND like before.

Then I need to set up a voltage divider (10k resistor in series with 20k resistor to ground, which will give me Vout=3.3v) from TX on the Arduino to RX on the WiFly. Would I also need one going from TX on the WiFly to RX on the Arduino? I'm assuming the WiFly works by setting TX to OUTPUT and RX to INPUT. So when it sets TX to HIGH that's 3.3v which is enough for the Arduino to read HIGH on RX with no problems?
#115263
Hmm. So I followed the directions for powering the WiFly right from the manual:

Apply 3.3 VDC power to VBATT (pin 20), and V3.3IN (pin 21).
Tie 3.3VREG-IN (pin 18) to GROUND.
Leave 3.3V-REG-OUT (Pin 17) floating/no connect

Then I just connected Gnd on the WiFly to Gnd on the Arduino. So basically I have 2 3.3v lines going into the WiFly (VBATT, V3.3IN) and 2 ground lines (3.3VREG-IN and Gnd). I confirmed the voltages there.

I left TX and RX unconnected for now and instead just supplied 3.3V to PIO9 to try to create and Adhoc network. When I turned it on, nothing seemed to happen. I couldn't find with network with my phone and there's what looks like a LED on the WiFly that I assumed was power which doesn't light. I also tried testing the voltages on PIO4, PIO5, and PIO6, and 3.3V-REG-OUT and got nothing.

Am I doing something wrong? Did I manage to break this thing already?

[edit] Nevermind! Apparently trying to make connections to the breakout by sticking jumper wire through the holes into a breadboard doesn't work very well. It's working now :)