Using a USB Keyboard without the use of a PC

Hi, I'm currently doing a project that involves a USB keyboard which is interfaced using a USB Host Shield then the output is displayed in an LCD. It is working fine given that the microcontroller is connected to a PC and a running serial monitor. My question is how can I make use of the USB keyboard WITHOUT plugging my prototype to a PC ?

TAKEN:
Hi, I'm currently doing a project that involves a USB keyboard which is interfaced using a USB Host Shield then the output is displayed in an LCD. It is working fine given that the microcontroller is connected to a PC and a running serial monitor. My question is how can I make use of the USB keyboard WITHOUT plugging my prototype to a PC ?

If the output is displayed in an LCD, why do you need the serial monitor?
Which Arduino are you using?

I have achieved what you want. If you don't want to plug your prototype to a PC you have to use an external supply for powering the Arduino.
You just need an input (Keyboard and usb shield), an output (LCD) , an external supply (AC/DC adapter 9V) and the Arduino.

If the output is displayed in an LCD, why do you need the serial monitor?
Which Arduino are you using?

I have achieved what you want. If you don't want to plug your prototype to a PC you have to use an external supply for powering the Arduino.
You just need an input (Keyboard and usb shield), an output (LCD) , an external supply (AC/DC adapter 9V) and the Arduino.

I see, the Arduino just fooled me.haha BUT it's inconsistent because most of the time the key is not sent and displayed in the LCD and testing it I think it is not initializing during the time I run "Usb.Task()" and get inputs from the USB keyboard.

I did a trick that worked for me, I plug the usb keyboard AFTER I power up the Arduino.

Hi, can I follow-up on this problem. I can only use the USB keyboard once, the Arduino has to be turned off or reset (does not always works). Most likely, there is an error: "OSC did not start. arduino". Does anyone has a solution in restarting the usb host for the USB keyboard?