few days ago the USB jack of my arduino stopped working, but the arduino itself works correctly. Is there a way to upload code via serial connection (in my case, using an EIA rs-232 port)?
I tried to connect the second pin of the serial cable to rx, the third to tx and the fifth to the arduino GND, but it doesn't seem working.
sorry for my English, actually i'm Italian
You should remember a few things.
First is that the voltage levels of pc serial ports are different from the 5 volts your Arduino uses.
Best way to make these connections, is to use a small pcb that makes the correct levels for both.
The the names of the ports are respective to the ports themselves.
So if you connect your PC's port pin 2 to rx pin of your Arduino, both devices are listening and none is sending.
Connecting pin 3 to TX means both are sending and none is receiving.
So you need to cross these wires.
2 to TX and 3 to RX.
The USB connection on your Arduino also resets it when a serial connection is started.
That reset is needed by the IDE to know when to start sending data.
But you can try to send your sketch, and when you see the IDE actually starting the transmission, push the reset button yourself.
You might need to try a few times this way.
Your English looks fine to me (it isn't my 1st language either).
Hi MAS, thanks for you reply
Meanwhile, i changed my approach to the problem.
I recovered an usb connector connected to a ttl, that gives me four cable as output: red (the +5V, not used by me), black (GND, connected to the GND of the arduino board) and white and green (I suppose respectively TX and RX of the serial communication, so i connnected the white to RX and green to TX). The code uploading doesn't work, even if I swap the position of the white and the green cable. Maybe I press with the wrong timing the reset button: exactly when I should do it?
Newer IDE doesn't start uploading right away, it will always compile first (even if you compiled / checked it right before you clicked the upload button).
The blue status bar beneath the code and above the black feedback window (i don't know what it is called exactly) shows you when the upload starts.
Immediately when that is shown, press the reset button.
If you have a multimeter, use it to see what levels you've got on those white and green wire, without the connection to the Arduino board.
Measure it with your black test pin to the black wire.
If you have no voltage, you might need to connect the red wire to 5 volts (of your Arduino).
You can also measure that red wire to see if it has the 5 volt USB power.
As you hit the compile & upload button in the IDE hold down the reset button on your arduino. As soon as you see "Binary sketch size:" release the reset button. Another way is to watch the wording that just above where the Binary sketch size: appears and when it changes from Compiling to Uloading release the reset button.