command button

Hi,
I have a form with command buttons and i want to input a number (ID from a Product), that is written on that command button, in a control in a subform. I can input the number - Me.[subform_control_name].Form.[control_name] - but i can´t get the cursor active on any control of the subform, so, when i press Tab the cursor is on other command buttons of the form, but not in the subform fields.

I have already used the intruction Me.[subform_control_name].Form.[control_name].SetFocus but i only get the field highlightened not a cursor blinking. So i can't write unless i click the field with the mouse cursor.

I want to use the command buttons as they work in the software "WinRest" (used in restaurants to do the bills...), in order to input the code from a Product and then activate a query. I do not know if it is possible to do this in Visual Basic for applications ?

Thanks