Preparation
- You need a
Serial Debugging Tool
. In this guide, we will use aUSB to TTL Converter
. You can find a CH340 USB to TTL Converter here.
Connections
Follow these steps to make the correct connections:
Connect the Tool Pins to the GPIOs, and check the Tx / Rx Pins once more to ensure that you’ve made correct connections:
- Tool Pin
GND
: <—>Pin17
of VIM’s GPIO - Tool Pin
TXD
: <—>Pin18
of VIM’s GPIO (Linux_Rx) - Tool Pin
RXD
: <—>Pin19
of VIM’s GPIO (Linux_Tx) - Tool Pin
VCC
: <—>Pin20
of VIM’s GPIO
- Tool Pin
Insert the USB-end into your PC.
The connections should look like this:
- Blue color line: Tool Pin
TXD
- Orange color line: Tool Pin
RXD
- Black color line: Tool Pin
GND
Another photo for more details (VCC
Pin is not necessary):
Setup Serial Communication Program
On Ubuntu system, you can use minicom
serial communication program.
- Install
minicom
1 | $ sudo apt update |
- Add access permission
1 | $ sudo usermod -a -G dialout $(whoami) |
You may need to logout or reboot your system.
- Setup
minicom
Before setup minicom
, you need to connect the USB to TTL Converter
tool to your device and computer.
1 | $ sudo minicom -s |
You will enter minicom
setup mode, like this:
1 | +-----[configuration]------+ |
You can use up/down arrow on the keyboard to shift to Serial port setup
item and hit Enter
to Serial port setup
menu.
1 | +-----------------------------------------------------------------------+ |
You can use Shift + A
to setup the serial device, and hit Enter
to confirm.
You can use Shift + E
to setup the baudrate, choose 115200
and hit Enter
to confirm.
You can use Shift + F
to disable the hardware flow control, set to NO
.
When you done all the setup, you can hit Enter
to exit the menu, and then choose Save setup as dfl
to save the configuration, then Exit from Minicom
.
NoteYou need to replace the serial device node to the correct one on your computer.
- Launch
minicom
Type minicom
command in terminal will enter the board serial terminal.
1 | $ minicom |
- Exit
minicom
You can use Ctrl + A + Z
to lanuch the menu:
1 | +-------------------------------------------------------------------+ |
And use Shift + Q
to exit minicom
.
1 |
|
Choose Yes
and hit Enter
to exit minicom
.
Tips
If the terminal output contains this line, you might need to type
sudo minicom
.
1 /dev/ttyUSB0: Permission deniedTo access U-boot, leave your USB-Serial-Debug tool connected, then press the
reset
button on your device once. You should see some print-out on your terminal, then quickly press thespace-bar
orcontrol-c
to stop auto-boot. You will see the prompt kvim# when you’ve entered u-boot.Note that to see the standard “help” commands as listed in the U-Boot Usage Guide, you’ll need to first have a version of Android or Ubuntu installed in your VIM device, from our krescue images.
You can use the U-Boot command line (kvim#), to change your VIM’s default boot logo.bmp, according to the guide, Boot Logo for U-Boot.
See Also
On Windows system, you can use SecureCRT
serial communication program.
- Install USB to TTL Converter Driver
If you haven’t install USB to TTL Converter
driver, you need to install it. Here we take CH340 as a example.
- Download the driver here
- Unzip the file
- Run the installer which you unzipped
- Install
SecureCRT
Please access SecureCRT official website to down and install it.
- Setup
SecureCRT
Before setup SecureCRT
, you need to connect the USB to TTL Converter
tool to your device and computer.
Launch SecureCRT
and navigate to File->Quick Connect
:
Select protol Serial
, and select correct device node, baudrate set to 115200
, unselect XON/XOFF
.
Then click Connect
will enter the board serial terminal.
On Mac OS system, you can use minicom
serial communication program.
- Setup the terminal
As minicom
need Meta key, so you need to setup your terminal Meta option.
Go to Terminal->Preferences->Keyboard
, select Use Option as Meta key
.
- Install
minicom
You may need to install homebrew if you haven’t instll it.
1 | $ brew install minicom |
- Setup
minicom
Before setup minicom
, you need to connect the USB to TTL Converter
tool to your device and computer.
1 | $ minicom -s |
You will enter minicom
setup mode, like this:
1 | ┌─────[configuration]──────┐ |
You can use up/down arrow on the keyboard to shift to Serial port setup
item and hit Enter
to Serial port setup
menu.
1 | ┌───────────────────────────────────────────────────────────────────────┐ |
You can use Shift + A
to setup the serial device, and hit Enter
to confirm.
You can use Shift + E
to setup the baudrate, choose 115200
and hit Enter
to confirm.
You can use Shift + F
to disable the hardware flow control, set to NO
.
When you done all the setup, you can hit Enter
to exit the menu, and then choose Save setup as dfl
to save the configuration, then Exit from Minicom
.
NoteYou need to replace the serial device node to the correct one on your computer.
- Launch
minicom
Type minicom
command in terminal will enter the board serial terminal.
1 | $ minicom |
- Exit minicom
You can use option + Z
to lanuch the menu:
1 | ┌───────────────────────────────────────────────────────────────────┐ |
And use Shift + Q
to exit minicom
.
1 |
|
Choose Yes
and hit Enter
to exit minicom
.