Setup Serial Debugging Tool


  • [x] A Serial Debugging Tool, what we used in the guidance is an USB to TTL Convertor, ensure it supports 1500000 baudrate.
  • [x] For Edge need Edge IO board to support serial debug.


Follow the steps to do the connections:

1) Connect Edge IO board to Edge via FPC connector.

2) Connect all the GPIOs, and check the Tx / Rx Pins and ensure done the right connection:

  • Tool Pin GND: <---> Edge IO GND
  • Tool Pin TXD: <---> Edge IO RXD
  • Tool Pin RXD: <---> Edge IO TXD

The connections should be like this:

Image of SerialConnections

3) Insert the USB to your PC.

Setup the Kermit Protocol(C-Kermit)

Install the c-kermit:

$ sudo apt-get install ckermit

Add the access permission

$ sudo usermod -a -G dialout $(whoami)

Add the following contents into ~/.kermrc to finish the setup:

set line /dev/ttyUSB0
set speed 115200
set carrier-watch off
set handshake none
set flow-control none
set file type bin
set file name lit
set rec pack 1000
set send pack 1000
set window 5

Run command kermit to launch C-Kermit

Ensure that you have done the right connection, and if everything goes fine, printing would be like this:

$ kermit
Connecting to /dev/ttyUSB0, speed 115200
Escape character: Ctrl-\ (ASCII 28, FS): enabled
Type the escape character followed by C to get back,
or followed by ? to see other options.
TE: 116640


Tips: If the printing contain following line, you might need to check the step Add the access permission above.

/dev/ttyUSB0: Permission denied

Enable 1500000 baudrate

In order to enable 1500000 baudrate, you need to repalce kermit binary, click here to download, and execute the following commands.

$ chmod +x kermit
$ sudo cp kermit /usr/bin/kermit

If you want to use 1500000 baudrate you need to modify ~/.kermrc speed to 1500000.

See Also