Redstone keyboard with 30 unique keys with a combined 5bit output bus. It has leters a-z labeled 1-26 in BIN, then space, backspace, ctrl, and shift labeled 27-30 in BIN. The delay for each key is 3-5 redstone tick or about two char per second. The varying delay means if you type to fast there is a chance for charecters to get jumbled, so the noteblock should be used as an indication that the user can press the next buton. It's pretty much fully spam proof, unless you empty the slot completly(don't do that).



Also, some things worth noting is the item refill is not 100% fullproof so some items may leak to that chest at the end so some maintanance is required.