> Being 5V tolerant doesn't mean that your 3V output can sufficiently drive an input that expects 0-5V levels correctly. It's fine for TTL (like your 74LS245 i

> Being 5V tolerant doesn't mean that your 3V output can sufficiently drive an input that expects 0-5V levels correctly. It's fine for TTL (like your 74LS245 is), which registers voltages as low as 2V as a logical 1. Being able to directly interface with TTL eases up so many retrocomputing applications.