How to use
Last updated
Last updated
Already flashed Jetson
Carrierboard that supports UART
UART cable to connect to the carrierboard
The loopback is mostly used for testing the TTY interface and is a good start to get used to it. Its only required to connect one cable from the UART TX to the UART RX signal.
If you want to communicate between two system, then you have to connect the UART RX and TX signals crossed with the ones from the other signal.
Don't forget to connect the ground. The power connection is only required, if your device is not externally powered.
Minicom is a terminal tool to simplify the configuration and the usage of the UART port that you want to use.
In case you do not have Minicom already installed use the following command to install it on your Jetson:
Each TTY device is mapped to a different hardware UART. This changes for each Jetson platform
Now that everything is set up get the debug logs, you just have to start Minicom with the following parameters:
Your terminal should now look like something like this
There is always a Start bit which starts with a low bit pulse and a Stop bit which stops with a high bit pulse. Between the Start and Stop bit are the programmable numbers of data bits (typically between 5 to 8)
Requirements:
RTS data line (Request to Send)
CTS data line (Clear to Send)
These lines are cross-connected between two devices. The RTS line is used to output if it is ready to accept new data and the CTS is used to read if it is allowed to send data to the other device.
Requirements:
RX (Receiver)
TX (Transmitter)
GND (Ground)
The Transmission in a Software Flow Control is started and stopped by sending special flow control characters. The flow control character are send from the Transmitter to the Reciever line.
Special flow control characters:
XON (Allow transmission from device, control character: DC1 ^Q, ASCII dec 17)
XOFF (Should halt transmission from device, control character: DC3 ^S, ASCII dec 19)
Example: Jetson 1 sending XOFF to Jetson 2 => Jetson 2 should halt transmitting to A until Jetson 1 sends XON to Jetson 2
The baud rate is the amount of bits that get transmitted per second.
Example: 1 bit per 200 millisecond is 5 baud
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Open you minicom terminal and press [CTRL-A] O to open up the configuration window
Press "Serial port setup" to continue
In this Panel you can configure:
Change Baudrate (E)
Toggle Hardware Flow Control (F)
Toggle Software Flow Control (G)
After changing your settings press Enter to save changes and go to Exit to close the configuration
| Hardware Flow Control | Software Flow Control |
|---|---|
Extra wires for Start/Stop transmitting
Special Character which are send over normal data line
