I was just wondering if there was rule to connecting rx and tx pins on different board or connectors. I have a camera and to connect it to arduino it should be connected as such
rx camera --> tx arduino
tx camera --> rx arduino
which I’m assuming is because whatever is sent from the arduino should be sent to the receiving end of the camera.
However, when trying to breadboard a barebones arduino using an usb-ftdi converter I wired it the same way and was wondering why the sketch was not uploading. So I switch the wires as such:
rx converter --> rx arduino
tx converter --> tx arduino
and it uploads. Is it just guess and check which order to wire the serial pins?
I’m sorry I wasn’t more specific. I have the camera connected using the softwareSerial library. If I designate say pins 2 and 3 as rx tx respectively pin 2 should go to tx of the camera and pin 3 to the rx of the camera. I’m making a barebones board and using an ftdi-usb converter to program it. I realize I cannot connect two serial devices to one set of pins. What was confusing me was why on some tutorials one ftdi converter might have this type of connection:
rx ftdi --> tx arduino
tx ftdi --> rx arduino
but on my ftdi converter the sketches do not upload unless I have the wiring as such:
rx ftdi --> rx arduino
tx ftdi --> tx arduino
I’m not having any problems. Just wondering why it’s sometimes like this considering I might spend an hour trying to debug wiring when all I had to do was swap serial connections.
The connections work this way… Rx goes to Tx and other wise…
Please check your software if you are assigning Rx and Tx correctly… Because these are not built in rx, tx pins… They are configurable by softwares…
Your connection seems right. If the Arduino transmits something on the TX line it needs to go to the RX line on the receiving end. However, the RX and TX lines in the Arduino are also used for programming; if you hook something to them, you can expect the programming not to work since the RX / TX lines are being used by something else which might be interfering with the communication.
In order to solve this problem you can simply disconnect the serial device when you program your Arduino and reconnect it when the program is loaded. Alternatively you could add jumpers to make it easier to disconnect or use the soft-serial library in order to use another set of pins to handle the serial communication.
