I created a WP8 App. It connects to the Bluetooth and detected it.and the Bluetooth module connected as well. But the data are not coming from the Arduino to the phone :(
error code
if(btSerial.available()) {
Serial.println(distance);
btSerial.write(distance);
}
else {
Serial.println("error"); -> always prints this
}
in the code always the error part is printing in the serial monitor. I have attached the pins in the Bluetooth device to below pins.
RXD - 11,
TXD - 10,
GND - GND,
VCC - 5v,
Please help me why is btSerial.available() is not firing ?
You have the logic backwards. available() tests whether the Arduino has data in its receive buffer. It does not test if the connection is ready. So the overall pattern of a serial program
if(someserial.available()) {
someserial.read... loop to get input
print stuff received
}
To write, just write.
//no if's just go
someserial.write("my output")
You do not need to wait. With the two wire serial connection, you have no flow control. In other words, there is no signalling between arduino and bluetooth transceiver about ready or other status. Because the baud rate of the bluetooth link exceeds the baud rate of the arduino serial link, you can't really overflow the bluetooth transmit stream.
The bluetooth aspect of negotiating the connection is meant to be transparent to the Arduino. In other words, your program is the same as if you where using a hardware serial port. If for some reason, you need details into the connection, there are special byte sequences that allow communication with the bluetooth hardware.
Related
Can I use UART on MSP-EXP430F5529LP from Energia in order to communicate on pins p3.3 and p3.4 (rx and tx respectively)?
I already use UART in order to communicate with my PC via USB. To do so, I use Serial.println() and such. Now that one UART is taken, how do I configure and use second UART to go to these pins? Or would it be better to rewire my Bluetooth chip (BlueGiga wt32) to some other pins?
Configuration aside, Serial does not seem to allow for multiple UARTs. How does it know which UART to print to?
For some reason, I could not find any manual on interacting with wt32 from Energia, or on interacting with multiple UARTs on Energia.
Edit: found this link: http://forum.43oh.com/topic/3942-stellaris-lm4f120-multiple-uart-problem/
only, incidentally, they say it does not work. Still, a lead.. but it is my understanding that I still have to configure UART on those two pins, if at all possible.
Edit2 Found MultiSerial example in Energia:
/*
Multple serial test
Receives from the main serial port, sends to the others.
Receives from serial port 1, sends to the main serial (Serial 0).
The circuit:
* Any serial device attached to Serial port 1
* Serial monitor open on Serial port 0:
created 30 Dec. 2008
by Tom Igoe
This example code is in the public domain.
*/
void setup() {
// initialize both serial ports:
Serial.begin(9600);
Serial1.begin(9600);
}
void loop() {
// read from port 1, send to port 0:
if (Serial1.available()) {
int inByte = Serial1.read();
Serial.write(inByte);
}
}
Now, this may sound like a really noob question, but where is my Serial1?? Is it somewhere on my pinout? The corresponding page in Energia manual is just a stub.
Now, this link: http://energia.nu/Tutorial_SerialCallResponse.html has a pinout according to which P1.1 is TXD, P1.2 is RXSD, which is something that I have not seen documented elsewhere. I suspect that it is assigned in this particular example, only I don't see the assignment in the code; also, I suspect that this is the backchannel, unless the switch is turned. Confused!
Edit3: found SoftwareSerial example that turns pins of your choice into a RX and TX. So at least I probably have a software solution. Of course, I'd prefer hardware. The manual for the launchboard says the hardware supports up to 4 serial ports, but how? Where are the pins?
Sorry I keep adding to this. I'll tidy it out when there is a solution.
If you dont need those uart pins to talk to the host you can remove the jumpers on that board that connect rxd and txd and then connect those to your bluetooth module.
Serial.begin(); works for backchannel UART pins(Txd,Rxd between target ic & debugger ic marked in white squares in below image)
http://energia.nu/wordpress/wp-content/uploads/2015/03/2016-06-09-LaunchPads-MSP432-2.0-%E2%80%94-Pins-Maps.jpg
Serial1.begin(); works for P3_2 & P3_3
My problem is there was a spark when I plug in the voltage source of my 220 V bulb.I have my arduino uno r3,hc-05 Bluetooth Module,Relay Module and 220V bulb.
I cut the wire of my 220V Bulb.
One wire that is near to the bulb was connected to (COM)common connection of our relay.
The other cut was connected to ground.
The Relay Module's VCC was connected to Arduino's 5V.
The Relay's input pin was connected arduino's pin 13 as well as the Normally open(NO) pin of reay.The Relay's ground ws also connected to Arduino's ground.
My Bluetooth module tx was connected to aruino's rx ans Bluetooth module's rx was connected to tx.
I also connected Bluetooth Module,5v to the Arduino's 5v.
and A ground from Bluetooth module to Arduino's Ground.
I made my own version of schematic diagram and this is how it works.It is not that nice but I hoope you will understand.
The small squares serve's as the BreadBoard
https://twitter.com/n_galia/status/419876079403147264/photo/1
Here is a simple relay driver you can use with the Arduino. The component values are not super important, R4 could be larger, R3 can be larger, you can use just about any 5V relay and any NPN transistor. As show it should work with most low/medium sized relay. When active you can check the voltage between Q1's collector and ground. It should be less then a volt. About 4mA is provided by the Ardunio, far below it's output capacity.
PLEASE BE CAREFUL!! you are working with high current and high voltage power. Blowing up an Ardunio is minor compared to the damage you can do to yourself.
The revised schematic might not work either. If your relay is a basic relay a driver will be required. The Ardunio can only sink about 20mA and it's likely your relay will need more to function correctly. The relay coil might look like a short to the Arduino.
If you have a relay with a built in logic level driver or a solid state relay, or even a TRIAC part (not a relay) you might be OK.
In situations like this its advised to use an optical coupler between the Arduino and the relay.
The optical coupler has a transistor that will dive the relay in its output, the transistor is actually a light sensitive transistor (photo-transistor) which is turned on via an LED built into the package. The Arduino would drive this LED (though a limiting resistor) which would activate the transistor to drive the Relay. This way the low voltage electronics are totally protected and isolated from the high voltage stuff.
Ouch!
The Arduino is not compatible of dealing with your 220Vac lines from power and to the light.
Your Arduino may not function correctly anymore.
I have attached a revision to your wiring.
I am new to Arduino and I have 2 issues when I tried the BluetoothShieldDemo.
I can only send data from bluetooth module(through serial monitor) to phone but I cannot send from phone to bluetooth module(to display it in serial monitor). I used oscilloscope to check there is signal in the Arduino board RX pin but no data display in the serial monitor. I suspect it is an IO issue so I changed the IO from digital pin 6 and 7 to digital pin 2 and 3, then digital pin 4 and 5. But it is still not working. Then I change the code to use hardware serial (Serial1) and it is working now. I just wonder why it is not working with the SoftwareSerial.
Although I can send and receive data, I cannot change the bluetooth name. The bluetooth module has no response when the below commands are sent. Is it the bluetooth module is in some kind of locked mode? Or the command is different from manufacturer? The bluetooth module that I got has a single CSR 31A2 chip on it. But the other shield that I saw on the web has 2 chips and it is with CSR BC417.
Codes:
blueToothSerial.print("\r\n+STWMOD=0\r\n");
blueToothSerial.print("\r\n+STNA=BluetoothSlave\r\n");
blueToothSerial.print("\r\n+STOAUT=1\r\n");
blueToothSerial.print("\r\n+STAUTO=0\r\n");
delay(2000);
blueToothSerial.print("\r\n+INQ=1\r\n");
Thanks in advance!
1- When using SoftwareSerial, how are you declaring the pins (Input/Output)?, Are you pulling serial data right (giving it enough time between data transmission, but reading at the right time)?
2- Find the datasheet of your module and see what commands does it support.
I'm working on a project with Android and Arduino and am trying to figure out how on the Arduino side to tell if the Bluetooth is connected or not.
I'm using one of these Bluetooth Modules to connect. I know I can send a command through Android, but I'm trying to have an action happen automatically when they connect and not have to run a background application on the Android if possible.
Using the module supplied and nothing else you cannot: notice the module has four connectors:
Power (Vcc)
Ground
Tx (send)
Rx (receive)
Given this interface the only way to determine whether the bluetooth module is paired is to send something to the paired device and have it respond in such as way that your Arduino knows that it is connected. For instance, if your Android program always responds with "Hi there!" when it receives a string "Hello?", then by seingin "Hello?" your Arduino will know that it is paired with your Android phone/tablet. Your Arduino could poll (send the interrogation string) every minute (or every five seconds) to see if it is paired with your device.
There is a better way, but it will require some soldering on your part. If your module is HC-03/HC-05-based, then the PIO9 pin is the "paired indicator LED" (see datasheet here). You could connect that pin to an Arduino input pin and read the level: reading digital 1 will indicate that the device is paired, while reading digital 0 will indicate that it is not. It is possible, though not certain, that the pin on your module labeled STATE is exactly this kind of a pin, i.e. it indicates the paired status. Unfortunately. this pin it isn't connected to the header, so you'll have to solder a wire to the correctponding pad to connect it to your Arduino. You should test it first by connecting a multimeter in voltage mode to that pad and measure the potential between that pad and ground in paired and non-paired state. If this is the pin that responds to the paired state then you are golden. It might be that it indicates power (like the HC-03/05 PIO8 whilc blinks when on). If it turns out that the STATE pin is not the pairing status, then you should request a datasheet from your supplier, and use that to find the status LED connection: one is likely to exist. Once you found the correct pad, verify its function using the voltmeter again. Then solder a wire to that connection and read it from your Arduino.
IMPORTANT: Make sure that your Arduino never puts out a digital 1 on the Arduino pin connected to the bluetooth module status pin: these bluetooth modules run on 3.3V, and connecting any unprotected pins to 5V will be damaging. The Vcc and Txd pins are voltage shifted in the module you bought, but the LED/Status lines are likely not to be. So if the Arduino pin connected to "status" on your Bluetooth module is configured as output and you digitalWrite(HIGH) to it, you will likely damage the Bluetooth module.
Unfortuntaely, the HC-05 will switch states when paired, but won't output a 1 until it's actually connected to something.
For instance, I can unpair my phone from the HC-05, pair again, and then the LED will change state, but the output of the STATE pin is still 0. If I open up an app, and connect to the device manually then the LED, and STATE pin will change state. The LED will periodically blink twice, and the STATE pin outputs a 1 to the Arduino.
If you would like to read the the value of the STATE pin, connect a wire to any of the inputs to the arduino, and code Serial.println(digitalRead(inputPin)); inputPin being the wire to the input of the Arduino.
I've been fighting this thing for months, and have yet to find a way to make this thing automatically connect to my phone. It won't even allow for me to connect to it from my phone to the HC-05 unless I download an app onto my Android. It's possible to bind the HC-05 to a certain address, but even this did not work for me. I want to mess with the "AT+CLASS" command, but the documentation behind the instruction has hindered me thus far.
From the HC-05 datasheet we see that the connection status depends on the output from PI09. Apparently sending "AT+BIND?" to the module will return the status of PI08 & PI09 in the form,
"+ POLAR=PI08,PI09" however this makes no sense to me because in order to get this you must enter AT mode and entering AT mode will disrupt the paired connection, hence it will always send PI09 marked as "not connected".
THUS in order to see if the connection is still live from the arduinos POV I can only see 2 feasible ways:
Program arduino to, every so often, send a "hello?" and if it doesn't receive the expected "Hi back" response, then it is to assume that it isn't connected.
Connect PI09 to an arduino input pin and read it's value whenever you want to check if the connection is live or not
AT+STATE? will return the current state of the connection. Yes you will need to enter at mode, that is done by bringing up pin 11 HIGH on the HC05 module. It does require soldering but it's kinda worth it. It then allows full AT control of the device, then set it LOW to return it to normal working mode.
Another option, which I don't fully understand, is the AT+MPIO? command, which returns the state of all the pins in some strange masked format I don't understand yet.
I use the first option above so that I can terminal (Bluetooth) from my phone to the HC05 and switch on a led/relay etc (ie bring up pin 2 to HIGH) on the HC05. This required entering AT mode (pin 11 HIGH), sending the command AT+PIO=2,1 and then setting pin 11 to LOW to return to normal working mode.
Note: I noticed I had to put a 200ms delay in between high and AT and LOW commands. Angela's solution is nice - I use a cheap XBEE Bluetooth module (HC-05 Bluetooth Bee Master & Slave Module with Bluetooth XBee for Arduino uk2015) 2 units(HC05/6) for 5Stg which are laid out in XBEE format - handy for the 3.3v.
I use Arduino for comunication between sensors and my C# application using a serial port. Is there any possibility to access digital components directly such as Force Sensitive Resistor - Square, from a USB port?
Do I have to write a driver for that?
I drew a semi-schematic diagram to exemplify:
There isn't a way to directly read an analog sensor over USB since it's a digital bus. You need some sort of processing to convert the analog signal to digital and communicate over the bus properly.
In order to sample information from any sensor, you will need an intermediary. The Arduino uses an FTDI chip to convert UART (Serial) to USB. When you read data over this connection, you are reading it over the Serial over USB interface. My recommendation is to stick with using the Arduino or other micro controller.
If you are really bent on reading it Directly over USB (instead of through the Serial over USB converter) you would have to implement some sort of protocol in a device that supports USB such as the Stellaris Launchpad or an Atmega32U4 AKA Arduino Lenardo. You would also have to write a driver to describe how to communicate with this USB device. Unless you were able to implement it as an already known device such as a keyboard or serial port (Yep, we went full circle there).
In short, there's no already made chip that converts Analog (or Digital) values from a sensor into something any OS would natively understand. Since USB is a protocol much like IP, you're not going to be able to use discreet devices. You're going to have to use a micro-controller with a USB stack.
Again, my advice would be to pass the sensor values over USB through the existing Serial (over USB) port. This is pretty straight forward and easily reproducible without an entire Arduino.
From the looks of the force-sensitive resistor, this is an analog component; the resistance and capacitance changes with the force applied to the sensor. If you check out the FSR installation guide document there are suggested electrical interfaces starting on page 16.
I would recommend the first circuit, connect Vout to an analog input on the Arduino. From there you will need to convert from ADC counts to voltages and then use a lookup table function in the Arduino to convert from voltage to force according to Figure 9. At this point you have a variable containing the force applied to the sensor. From here you can transmit the value over the USB serial bus just like any other value. Your C# application then needs to read the serial data, and parse out the value.