In a block cipher you should be able to work with 256 bits at a time. You'd be typing 32 characters at a time (assuming ASCII) which get written out at once after you've somehow derived a secure key.
It's not like you can get much feedback from the system in its weird encryption mode either as it's typing out garbage, unless you teach yourself to decode the message from the top of your head (but at that point you don't need the machine to encrypt for you).
It's not like you can get much feedback from the system in its weird encryption mode either as it's typing out garbage, unless you teach yourself to decode the message from the top of your head (but at that point you don't need the machine to encrypt for you).