Arduino Nano & Bluetooth Mate Silver project

Hello!
I'm making a project. It's a device which is measuring force and skin conductance. So i'm reading force sensor and what comes from electrodes. I have some problems and i would be thankful if you could help me...

  1. I tried to send data from Arduino to my computer via bluetooth. When i open serial monitor the green conect led on modul starts to light.But i'm not getting any data. I set the baud rates to 115200 everywhere. I connect mate to arduino-->RX-TX,TX-RX and i'm powering it with 5V. Do you have any ideas what else to try?

  2. I don't know which way to power everything. I'm thinking of lilyPad voltage regulator(1.5V AAA batery with step up regulator to 5V). It can provide up to 100mA. Mate needs 50mA and arduino(i guess) 25mA. Powering the circuit for sensors it's aprox. 1mA. I don't know which AAA rechargable battery to choose? I couldn't find the data about capacity of alkaline batteries..

I'm really pissed off especialy because of the blueetooth connection which i'm trying to establish for more than 3 days... :~

When i open serial monitor the green conect led on modul starts to light.

Which module?

I connect mate to arduino-->RX-TX,TX-RX and i'm powering it with 5V. Do you have any ideas what else to try?

Connecting grounds.

  1. I don't know which way to power everything.

USB, batteries, and wall warts are the usual choices. Solar is a bit too limited.

I'm thinking of lilyPad voltage regulator(1.5V AAA batery with step up regulator to 5V). It can provide up to 100mA. Mate needs 50mA and arduino(i guess) 25mA. Powering the circuit for sensors it's aprox. 1mA. I don't know which AAA rechargable battery to choose? I couldn't find the data about capacity of alkaline batteries..

Forget it. You'll burn through batteries in nothing flat. Use 4 AA batteries, instead.

  1. The green connect led on Bluetooth Mate Silver modul.
  2. I also connected the grounds.
  3. Another way i'm thinking is 3.7V 900mAh LiPo battery with step up regulator to 5V which can provide up to 200mA.
  1. The green connect led on Bluetooth Mate Silver modul.

I clicked that link. Nothing happened. I guess that means you can't use that module.

Does that module have any AT commands that sets the baud rate internally? You might be setting it in the arduino code and on the serial monitor but if the internal default is set to 9600 then your not going to get the correct data or anything anything at all.

The default baud rate of this modul is 115200. I set the baud on serial monitor and aswell in the arduino code to this speed. It's interesting that the connect led is on but it's not getting any data. I tried the same code over the usb and it was working.
This code:

/***********************
Bluetooth test program
***********************/

int counter = 0;
int incomingByte;

void setup() {
Serial.begin(115200);
}

void loop() {
// see if there's incoming serial data:
if (Serial.available() > 0) {
// read the oldest byte in the serial buffer:
incomingByte = Serial.read();
// if it's a capital R, reset the counter
if (incomingByte == 'R') {
Serial.println("RESET");
counter=0;
}
}

Serial.println(counter);
counter++;

delay(250);
}

I wrote to the sparkfun.com support so i hope i will get some useful answers.
I checked this blog but i didn't find what could be wrong...
Bluetooth Mate Tutorial

Most Bluetooth modules work better at 3.3volts try that. I have a JY-MCU module that goes on at 5V but won't send any data. But it I put it to 3.3V, it works fine. Try that.

Aha ok. So i can still power the Arduino with 5V. Just the modul with 3.3V?

Are you powering the arduino with the Vin? It would be better to power it from the regular plug, and use the 3.3V that the arduino supplies. Of course that would mean a battery with more voltage (7 - 12V) but you would need to buy any regulators.

It's what ever you decide to do, it is your project.

you can always test the bluetooth module with the USB in the arduino, and just power the bluetooth with the 3.3V like that.

I'm powering arduino with regulated 5V(pin 5V). If i would power arduino with usb and then use output pins(regulated 5V or 3.3V) there will be a problem because there is max. current on the pins(40mA). Bluetooth modul needs max. 50mA.

The 5V and 3.3V are not limited to 40mA. They are limited, but have higher limits. You can read the limits for yourself, for your board.