The four registers each have a set and enable switch, the enable is the one with the switch. You don't need to switch the 1 to 0 just turn the switch on or off. The set is the other number. Here you do need to switch the number. The number at the way top is acting like Input from the computer. You can copy information from the computer input or from register to register. But remember to always keep at least 1 of the 5 switches on or else the power will be lost and information in the registers. Each register is hooked up to the binary to hex box, so you can play with making numbers by copying 1s and 0s from computer input or from register to register
