Trouble with button control

Hi,

I am using a program which reads the voltage from my usb device and displays it on the screen.

The voltage value is updated only when i click the button.

I want the voltage to be updated continuously when i click the button once.

BUT,

When I add a loop to inside the function of key switch the program displays only one value but after the certain loop is run.

But wen i click continuously

on the button without loop at very high  speed it updates properly.

Any Suggestions. I ve used timer, all loops to check.

 Dim areadpending As Boolean = False

    Private Sub rwButton_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles rwButton.Click, rwButton.Click


        areadpending = True
        readr()




    End Sub


Private Sub readr()

        FindTheHid()
        ReadAndWriteToDevice()

    End Sub