Hello. I have deployed Arduino devices in several place in order to supervise the temperature in places and in 1 place, I’m facing a pb 1 or 2 days after I have installed the board. I would like to use the Serial Monitor available in Arduino IDE to trouble shoot without having the board connected to my PC because I cannot leave my PC in a rooms for several days (remember that the pb doesn’t happen at the beginning, but after 1 or 2 days I have swithed on the board).
I thought that using a USB/TTL devices, connected to my PC and to the Arduino via TX/RX would be fine (the Arduino board receiving the power via the USB board connected to the electrical power).
But when I try to use the Serial interface, I have an error message : “board not connected to the COM3”… and that normal because it is not.
And so the question is : how to use the Serial Monitor only to trouble shoot ?
Connection is as follows :
Electrical plug > Arduino USB (that’s OK as the Arduino is working)
Arduino TX/RX > TTL – USB board RX/TX > My PC USB (software = Arduino IDE Serial monitor)
Hi : let me rewrite the needs : for trouble shooting purpose, I would like to be able to receive on my PC the text that the board Arduino is sending using the “Serial.print” commands, not having the board connected to the USB interface of my PC.
Usually, when I connect the board to the PC with a USB link, I can see, using the Serial Monitor tool, the text the board is sending.
But here, in my situation, the board is connect via the USB to an electrical plug, not to the PC.
And so the question is : how to connect the board to my PC to be able to receive on my PC and the text the board is sending with the Serail.print commands.
I was wondering it is would be possible to connect my PC to a USB to TTL Converter, that would be connected to the Arduino to do so, and to receive the data in the Serial.monitor tool (through my COM3 interface). But is is not possible as the Serial monitor tool needs to have the board connected to the COM3.
May be with a TTY monitor on my PC connected to the USB/TTL converter ?
Ok, so you are using the USB port to power the Arduino from a charger or power adapter so the port is otherwise occupied and unavailable to be used for data.
Here you loose me a little, but, since your USB port is in use for power and unavailable for data, this means finding another way for the Arduino to communicate with the PC to transfer data. This can be done using a USB/TTL converter as you suggest, for example, one of those FT232RL boards you can get on eBay. Since there is no data connection happening via the on-board USB port, you should get away with connecting the converter to the Tx/Rx pins of the Arduino. You will, of course, also want to connect GND.
When you connect this new interface to the PC, it may be assigned a different COM port in Windows, say COM4 or COM5 or something else instead of COM3. This can be checked in Device Manager in Windows. Once you have established which COM port it is on, it should be possible to connect to this with any suitable terminal program such as PuTTy or even Serial Monitor within the IDE by specifying the correct COM port and baud rate.
You won't be able program the board unless you also make an additional connection, but you should be to see the output from the Arduino.
If you don't want to use Tx/Rx for some reason, then you can also use SoftwareSerial to assign a couple of GPIO pins as a serial port, but you will have to amend your code to send to the SoftwareSerial port instead of 'Serial'.
I am not sure quite what you mean by this as Serial Monitor in the IDE is essentially a serial TTY terminal but like any other terminal program it does need to be pointed at the correct serial port. I am therefore wondering whether your USB/Serial TTL is actually coming up as a serial port on your PC? Which USB/TTL interface do you have? Did you or perhaps Windows auto install drivers for it? Did you check in Device Manager in Windows what COM port it is actually coming up on?
First question is what Windows device manager thinks about your TTL-to-USB converter. If it's not properly recognised (for e.g. one based on the CH340) you will have to install the drivers for it.
After that you will have an additional COM port that you can use in the IDE.
Hi.
You can use the on-board LED on your Arduino board to give you some information about what the program is doing. You could make it blink in different patterns to indicate different conditions.
Also, a bluetooth module such as HC-05 can send serial data to your PC or phone without needing a wired connection.
