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
Related
I'm creating a virtual serial port using socat.
socat -d -d pty,echo=0,raw pty,echo=0,raw
That works as expected so far. Using echo/cat I can send/receice text etc.
But what about signal lines like DTR or RTS? How would I get / set the state of these lines with a pty? Is that even possible? I couldn't find any mentions about it anywhere.
socat is a pipe handler, basically lets you tap in the Tx and Rx "lines" without you having to care about signaling when data is ready/received.
The RTS/CTS/DSR/DTR are actual pins in a serial connector that control what is going on on the Tx/Rx lines.
Off the top of my head, I haven't used socat nor tried to do anything similar, lowest possible level I got was the EMV interface and protocol and sometimes I also netcat stuff real quick between machines when I'm too lazy to cp to a directory within httpd home... anyway, if you are trying to connect two entities with socat (separate machines, or applications on the same machine) you'll either use the same pipe and specify some control characters so they end up talking at the same time (got to make a note of this and try to implement it somehow with my wife), or use two separate pipes, one for Rx and one for Tx: Tx of entity 1 goes into Rx of entity 2, Tx of entity 2 goes into Rx of entity 1.
From your comment, it sounds like you want to control RTS/CTS independent of your data stream. You will have to write an application to interact with the serial port using ioctls.
I found this helpful forum post (with an example application)
https://www.linuxquestions.org/questions/programming-9/manually-controlling-rts-cts-326590/
You can use hardware flow control lines (RTS/CTS):
socat stdio file:/dev/ttyAMA0,crtscts=1,b9600
Nowadays, this is mostly useful when talking to an RS485 transceiver, since that's the most common example of half-duplex serial line that is still in use. On some commonly used transceivers, such as the 75HVD12, the DE (drive enable) pin is connected to the host's RTS. There's also an active-low /RE (receive enable) pin that is connected to either RTS or CTS.
If you have access to GPIO, such as on a Raspberry Pi, you might be able to assign DTR and DSR to an output and input pin respectively. Alternatively, an USB adapter such as FTDI232 will assert DTR if it is connected to a computer.
Can anyone tell me why the characters are not getting printed properly in the serial monitor of Arduino? I am pasting the arduino code.
#include <SoftwareSerial.h>
#include <LiquidCrystal.h>
// initialize the library with the numbers of the interface pins
LiquidCrystal lcd(12,11,5,4,3,2);
int bluetoothTx = 15;
int bluetoothRx = 14;
SoftwareSerial bluetooth(bluetoothTx, bluetoothRx);
int incomingByte;
void setup() {
pinMode(53, OUTPUT);
Serial.begin(9600);
lcd.begin(16, 2);
lcd.clear();
bluetooth.begin(115200); // The Bluetooth Mate defaults to 115200bps
delay(320); // IMPORTANT DELAY! (Minimum ~276ms)
bluetooth.print("$$$"); // Enter command mode
delay(15); // IMPORTANT DELAY! (Minimum ~10ms)
bluetooth.println("U,9600,N"); // Temporarily Change the baudrate to 9600, no parity
bluetooth.begin(9600); // Start bluetooth serial at 9600
lcd.print("done setup");
}
void loop()
{
lcd.clear();
Serial.print("in loop");
//Read from bluetooth and write to usb serial
if(bluetooth.available()) {
Serial.print("BT here");
char toSend = (char)bluetooth.read();
Serial.print(toSend);
lcd.print(toSend);
delay(3000);
}delay(3000);
}
Can anyone take a look into it. It does not print the character that I provide instead it prints something else like 'y' with 2 dots on top etc. Tried almost all the available solution.
Your issues could be one of a couple things. First and easiest to check is COMMON GROUND. Did you connect just the RX and TX pins or also the GND (ground) pin? Make sure that the ground from the BT mate is connected to the Arduino ground.
If you have done that, then your issue is with the baud rate. I'm pretty sure that SoftwareSerial can't read at baud rates beyond 57600. Arduino.cc docs say it can read at 115200, but other places say it will only write up to 115200.
To test this, you will either need to change the settings for this on the Bluetooth Mate or use a Mega or Leonardo which will have a hardware serial port (other than the one used for USB) which you should be able to configure for 115200.
If you try it with hardware serial either on a Mega or just using an FTDI or something and the messages still look garbled then perhaps the bluetooth mate is not actually configured to talk at 115200 as it claims. Trying reading the docs or testing with other baud rates.
Check whether error is present due to one of the following reasons:-
1) You haven't given any command to exit from the data mode. After setting the baudrate to 9600, you are directly switching to loop. You haven't given the command to exit the command mode.
2) I too had the same problem when I was using RN171 Wi-Fi module. The cause of the problem in my case was because I was sending data to Wi-Fi module in integer format instead of uint_8. While reading from the Wi-Fi module serially with arduino mega, I was reading it in the format of characters.
You have to remember that int is actually signed 16 bit integer. So while sending data to your Bluetooth module you have to send it as uint_8 or ASCII values of the characters that you want to send. You should also read it in the same format as you sent it.
3) If these are not the error then as calumb said, there can be error in setting the bluetooth module in command mode. You haven't checked for reply from bluetooth module whether it is really in command mode or not. You must read an CMD reply from bluetooth module and at the end of every command a reply of ack to conform that its really done what you want it to do.
This may be because of Bluetooth parsing data simultaneously. when sending two different data at the same time this may happens. try to control your data flow.
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.
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.