comment: >
  
  Do I need 2 knobs? or just 1 knob is enough?
  I want to buy keyboard macro (Macropad) and there is a choice: keyboard macro with 1 knob or with 2 knobs but I don't know other use of knobs beside sound volume and scrolling 
  (I think scrolling not very useful in knob if I have mouse wheel). So is 2 knobs are useful or one is enough?
context: Is there a software available where I can check if all my switches are working? I use a tofu dz60rgb >
  
  You don't need software... you can just use an online checker, like the one on QMK config.   Or, just use a generic keyboard test site like this.