Total Control POS is able to show warning message upon swiping patron's card. the warning message is a customised message which could be allergy warning or proof of vaccination warning etc.
To set-up the warning message, edit patron profile then go to Contact tab and enable "Display warning on POS" option.
POS terminal can also display an image that is associated to the patron.
Some POS terminals display a short header by default. This needs to be disabled on TC Admin to display the image.
Login to Total Control Administration console then go to Setup -> Setup POS
Under POS terminals determine the POS type then disable the Short Header option in Terminal Types tab.