Setup Serial Debugging Tool


  • [x] A Serial Debugging Tool, what we used in the guidance is an USB to TTL Convertor.


Follow the steps to do the connections:

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

  • Tool Pin GND: <---> Pin17 of VIM1’s GPIO
  • Tool Pin TXD: <---> Pin18 of VIM1’s GPIO(Linux_Rx)
  • Tool Pin RXD: <---> Pin19 of VIM1’s GPIO(Linux_Tx)
  • Tool Pin VCC: <---> Pin20 of VIM1’s GPIO

2) Insert the USB to your PC.

The connections should be like this:

Image of SerialConnections

Another photo for more details(VCC Pin is not necessary):

Image of SerialConnections

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

See Also: