USB Host 2.0 serial data

Using Arduino Programming Questions
1

Is it possible to send a byte of data over the USB port on a USB Host Shield connected to my UNO R4 WiFi?

For example, I would like to like to effectively do a

Serial.begin(57600);

byte action_poundChest[] = {0xFF, 0x55, 0x21, 0xDE, 0x00, 0xFF};
Serial.write(action_poundChest, 6);

as sent to the hardware serial (which I have tried, but it does not work), but, send it to the UNO Host's USB port (USB does work running Python on a RPi)...

I have looked at all the examples included in the library but don't have the chops to decern the answer to my question...

Ultimately, what I am trying to do is send a packet to my robot which is looking for a USB connection - this scheme below works in Python PySerial on the RPi (but I want to do for Arduino Cloud for IoT - Alexa):

import serial

# open serial port
ser = serial.Serial(port='/dev/ttyUSB0', baudrate=57600, timeout=1)

# send command to bot
ser.write(b'\xFF\x55\x01\xFE\x00\xFF')
2

I have no knowledge of the shield (or the library). I think that you first need to determine what the USB chip on the robot is; you can run lsusb to find that info.

Looking at the library examples, there might be three options all called somethingTerminal (see also Possible to use USB Host Shield as COM port to open terminal interface? · Issue #678 · felis/USB_Host_Shield_2.0 · GitHub).

Based on the fact that your python code works with ttyUSBx, you can exclude the acm_terminal.