Need your help to connect USB Serial Com port on Meraki Mr33 for flashing by uboot

I have one usb serial Com port with color
line red 5v
line white RX
line green TX
line black GND

and i did Connect on UART (J6). P4 is closest to the J6 marking & Power plug on the board
from J6 with Black + Green + White then i did plup power for Meraki MR33 and open cmd input comment as topic advise but it show error., please advise me how to correct it ? --serial=com5 --write=mr33-uboot.bin
File "", line 1
SyntaxError: can't assign to operator

first of all, why com5? Type dmesg | tail in command line to see what device is assigned to your UART adapter after you plug it into the computer. Suppose it's ttyUSB0 (but use your own device name instead in following steps)

Now run a serial connection program, such as picocom with keys appropriate for your device, e.g. picocom -b 115200 /dev/ttyUSB0

When the program started and shows you that it's working, power the router up or if it's already on, power cycle it (pull the plug out for a second and plug back in)

You should see the messages from router serial console, which should look like more or less comprehensible English text, if you have set everything up correctly.

If you see garbage, then baud rate is incorrect, try 57600, 38400 and so on. Whatever baud rate is appropriate to your device.

Then you can paste the result using backticks to quote the code (hit </> button to insert them). You can censor the MAC addresses if you want.

After that we could troubleshoot your problem.