Finding out the serial ports

I have Rock Pi S V13, that has 4 UART ports.

I'm already connecting to the board via serial console on /dev/ttyS0.

How can I find out what are the other ports assignments/paths?

I have tried to use a Python script to detect the output by using an FTDI to USB board with no luck (the voltage and baudrate are correct).

The Python script taken from manual:

import serial
import time

# I've tried /dev/ttyS2 and /dev/ttyS4
ser = serial.Serial(port='/dev/ttyS4', baudrate=115200, timeout=0.1)
print(ser.name)

try:
        while True:
                ser.write(b'hello')
                time.sleep(0.5)
except KeyboardInterrupt:
        ser.close()

Running

Quote

ls /sys/class/tty/*/device/driver

outputs

Quote

 

/sys/class/tty/ttyS0/device/driver:
bind  ff0a0000.serial  ff0c0000.serial  ff0e0000.serial  uevent  unbind

/sys/class/tty/ttyS1/device/driver:
bind  serial8250  uevent  unbind

/sys/class/tty/ttyS2/device/driver:
bind  ff0a0000.serial  ff0c0000.serial  ff0e0000.serial  uevent  unbind

/sys/class/tty/ttyS3/device/driver:
bind  serial8250  uevent  unbind

/sys/class/tty/ttyS4/device/driver:
bind  ff0a0000.serial  ff0c0000.serial  ff0e0000.serial  uevent  unbind

/sys/class/tty/ttyS5/device/driver:
bind  serial8250  uevent  unbind

/sys/class/tty/ttyS6/device/driver:
bind  serial8250  uevent  unbind

/sys/class/tty/ttyS7/device/driver:
bind  serial8250  uevent  unbind

 

and

Quote

ls -l /dev/tty* | grep 'dialout'

outputs

Quote

crw-rw---- 1 root dialout 4, 65 Dec 23 11:44 /dev/ttyS1
crw-rw---- 1 root dialout 4, 66 Dec 23 11:44 /dev/ttyS2
crw-rw---- 1 root dialout 4, 67 Dec 23 11:44 /dev/ttyS3
crw-rw---- 1 root dialout 4, 68 Dec 23 11:44 /dev/ttyS4
crw-rw---- 1 root dialout 4, 69 Dec 23 11:44 /dev/ttyS5
crw-rw---- 1 root dialout 4, 70 Dec 23 11:44 /dev/ttyS6
crw-rw---- 1 root dialout 4, 71 Dec 23 11:44 /dev/ttyS7