Eeprom AdminPassword$ As String = "admin"
Eeprom UserPassword1$ As String = "1234"
Eeprom UserPassword2$ As String = "1234"
Public Authed As Byte = 0

Command &H23 &H04 Logout()
    Authed = 0
End Command

Command &H21 &H02 Login(Username$ As String *5, Result$ as Single, Password$ As String)
    If Username$ = "user1" and Password$ = UserPassword1$ Then
        Authed = 1
        Result$ = 1
    ElseIf Username$ = "user2" and Password$ = UserPassword2$ Then
        Authed = 1
        Result$ = 1
    ElseIf Username$ = "admin" and Password$ = AdminPassword$ Then
        Authed = 1
        Result$ = 1
    Else
        Result$ = 0
    End If

End Command

Command &H22 &H03 Password(Username$ As String *5, Password$ As String)
    If Username$ = "user1" Then
        UserPassword1$ = Password$
    Else If Username$ = "user2" Then
        UserPassword2$ = Password$
    End If
End Command

Command &H20 &H01 Calculator (S$)

    If not Authed Then Call Error (NotAuthorized)

    Private X As Long
    S$ = Trim$ (S$)
    X = EvaluateExpression (S$, 0)
    If Len (Trim$ (S$)) <> 0 Then Call Error (SyntaxError)
    If P1 = 0 Then S$ = Str$ (X) : Else S$ = Hex$ (X)

End Command