> Its presence as an entirely isolated unit within the machine is mandated by payment processors. It is a separately certified secure enclave that shields the c

> Its presence as an entirely isolated unit within the machine is mandated by payment processors. It is a separately certified secure enclave that shields the card payment authorization process from the rest of the system so your information, most importantly your PIN, can't leak. There's absolutely a way to get (non-sensitive) display output out of it so they can reuse the main screen for display at least (fast food self-checkout machines do this in my area - the status display from the card terminal is replicated on the main screen during the payment process).