williams-et-al-1983-apple-ii-computer-graphics

CHAPTER 2-COMPUTER PHYSIOLOGY 5ONE BITTWO CHOICES2 1TWO BITSFIRST BIT SECOND BITONONOFFONOFFONOFFOFFFOUR CHOICES2 2THREE BITSFIRST BIT SECOND BIT THIRD BITONONONONONONOFFOFFOFFOFFONOFFOFFONONOFFOFFOFFONOFFONOFFONOFFEIGHT CHOICES23Figure 2-1. Bit combinations.once each RAM bit is set on or off, it remains in that state until altered by acommand, or until the computer is turned off. (At which time the values inRAM are lost.) All of the computer' s impressive capabilities rely on thelowly bit. One bit is quite a long way from making a computer, just as onegrain of sand is a long way from being a beach. A bit, like a grain of sand,has little meaning individually, but when grouped with thousands of other·bits, together they are able to take on meaning and fo rm.Making It Happen with Ones and ZerosAs stated earlier, each bit will take on only one of two states, on or off. Inorder to facilitate discussion, if a bit is on, it is said to have a value of 1; abit which is off has a value of 0. Since each bit may only be 1 or 0, each bitconveys a very limited amount of information. In the example of your