Counters Questions

• Counters are generally decoded in order to determine their count state.
• Phototransistors have varying resistance from collector to emitter, depending on how much light strikes them.
• An asynchronous counter differs from a synchronous counter in the method of clocking.
• When a J-K flip-flop is used in a circuit, we only have to consider the level at J and K at the active clock edge to know the states of the outputs.
• The MOD number of a Johnson counter will always be equal to one-half the number of flip-flops in the counter.
• In a synchronous counter, each state is clocked by the same pulse.
• To design a divide-by-200 counter using synchronous counters, two 4-bit counters could be cascaded together to form an 8-bit counter.
• Another term used to describe up/down counters is bidirectional.
• A state diagram is a table of states.
• All flip-flops in an asynchronous counter change states at the same time.
• Cascade means to connect the Q output of one flip-flop to the clock input of the next.
• The concept of a counter to implement a digital one-shot using HDL is not used.
• A serial in/serial out shift register transfers data from one line of a parallel bus to another line one bit at a time.
• Basic counters can be cascaded in parallel to increase the number of data bits that the counter can handle.
• The serial in/parallel out shift register transfers data from one parallel data bus to another parallel data bus one bit at a time across a single line.
• In a full-featured counter in HDL, the concept of rolling over simply means the count sequence has reached its limit and must start over at the beginning of the sequence.
• A reliable method for eliminating decoder spikes is to use strobing.
• Dependency notation is no longer used.
• Most sequential circuits contain a combinational logic section and a memory section.
• The terminal count of a typical modulus-10 binary counter is 1010.